C# Writing Data to Word via Template

Project interface created based on reference download link: Method to automatically create Word document via template in C#, but the resource is a txt file, need to type the code manually, considered as practice.
Before starting, we need to install Microsoft.Office.Interop.Word from NuGet. Below is the code needed, just copy it directly. It is slightly different from using NPOI.

// report.cs
using System;
using System.Diagnostics;
using Microsoft.Office.Interop.Word;

namespace export_doc
{
    public class Report
    {
        private _Application _wordApp = null;
        private _Document _wordDoc = null;

        public _Application Application
        {
            get => _wordApp;
            set => _wordApp = value;
        }

        public _Document Document
        {
            get => _wordDoc;
            set => _wordDoc = value;
        }
        /// <summary>
        /// use template to create new file 
        /// </summary>
        /// <param name="path"></param>
        public void CreateNewDocument(string path)
        {
            KillWinWordProcess();
            _wordApp = new ApplicationClass()
            {
                DisplayAlerts = WdAlertLevel.wdAlertsNone,
                Visible = false
            };

            object missing = System.Reflection.Missing.Value;
            object templateName = path;
            _wordDoc = _wordApp.Documents.Open(ref templateName, ref missing, ref missing, ref missing, ref missing,
                ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing,
                ref missing, ref missing, ref missing);
            
        }
        /// <summary>
        /// save new file
        /// </summary>
        /// <param name="path"></param>
        public void SaveDocument(string path)
        {
            object fileName = path;
            object format = WdSaveFormat.wdFormatDocument;//save foramt
            object missing = System.Reflection.Missing.Value;
            _wordDoc.SaveAs(ref fileName, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing,
                ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing,
                ref missing);
            
            //close _wordDoc , _wordApp
            object saveChanges = WdSaveOptions.wdSaveChanges;
            object originalFormat = WdOriginalFormat.wdOriginalDocumentFormat;
            object routeDocument = false;
            _wordDoc.Close(ref saveChanges,ref originalFormat,ref routeDocument);
            _wordApp.Quit(ref saveChanges,ref originalFormat,ref routeDocument);
        }
        /// <summary>
        /// Insert value to bookMark
        /// </summary>
        /// <param name="bookMark"></param>
        /// <param name="value"></param>
        /// <returns></returns>
        public bool InsertValue(string bookMark, string value)
        {
            object bkObj = bookMark;
            if (_wordApp.ActiveDocument.Bookmarks.Exists(bookMark))
            {
                _wordApp.ActiveDocument.Bookmarks.get_Item(ref bkObj).Select();
                _wordApp.Selection.TypeText(value);
                return true;
            }
            return false;
        }
        /// <summary>
        /// insert table & bookmark
        /// </summary>
        /// <param name="bookMark"></param>
        /// <param name="rows"></param>
        /// <param name="columns"></param>
        /// <param name="width"></param>
        /// <returns></returns>
        public Table InsertTable(string bookMark, int rows, int columns, float width)
        {
            object missing = System.Reflection.Missing.Value;
            object toStart = bookMark;
            Range range = _wordDoc.Bookmarks.get_Item(ref toStart).Range;
            Table newTable = _wordDoc.Tables.Add(range, rows, columns, ref missing, ref missing);
            //set table format
            newTable.Borders.Enable = 1;
            newTable.Borders.OutsideLineWidth = WdLineWidth.wdLineWidth050pt;
            if (width != 0)
                newTable.PreferredWidth = width;
            newTable.AllowPageBreaks = false;
            return newTable;
        }
        /// <summary>
        /// merge cells
        /// </summary>
        /// <param name="table"></param>
        /// <param name="row1"></param>
        /// <param name="column1"></param>
        /// <param name="row2"></param>
        /// <param name="column2"></param>
        public void MergeCell(Microsoft.Office.Interop.Word.Table table, int row1, int column1, int row2, int column2)
        {
            table.Cell(row1,column1).Merge(table.Cell(row2,column2));
        }
        /// <summary>
        /// set table alignment vertical % horizontal
        /// </summary>
        /// <param name="table"></param>
        /// <param name="align"></param>
        /// <param name="vertical"></param>
        public void SetParagraph_Table(Table table, int align, int vertical)
        {
            switch (align)
            {
                case -1:
                    table.Range.ParagraphFormat.Alignment = WdParagraphAlignment.wdAlignParagraphLeft;//left align
                    break;
                case 0:
                    table.Range.ParagraphFormat.Alignment = WdParagraphAlignment.wdAlignParagraphCenter;//center align
                    break;
                case 1:
                    table.Range.ParagraphFormat.Alignment = WdParagraphAlignment.wdAlignParagraphRight;//right align
                    break;
            }

            switch (vertical)
            {
                case -1:
                    table.Range.Cells.VerticalAlignment = WdCellVerticalAlignment.wdCellAlignVerticalTop;//top align
                    break;
                case 0:
                    table.Range.Cells.VerticalAlignment = WdCellVerticalAlignment.wdCellAlignVerticalCenter;//center align
                    break;
                case 1:
                    table.Range.Cells.VerticalAlignment = WdCellVerticalAlignment.wdCellAlignVerticalBottom;//bottom align
                    break;
            }
        }
        /// <summary>
        /// set font name
        /// </summary>
        /// <param name="table"></param>
        /// <param name="fontName"></param>
        /// <param name="size"></param>
        public void SetFont_Table(Table table, string fontName, double size)
        {
            if (size!=0)
            {
                table.Range.Font.Size = Convert.ToSingle(size);
            }

            if (!string.IsNullOrEmpty(fontName))
            {
                table.Range.Font.Name = fontName;
            }
        }
        /// <summary>
        /// set outline border
        /// </summary>
        /// <param name="n"></param>
        /// <param name="use"></param>
        public void UseBorder(int n, bool use)
        {
            // allow has border , default no borders , 1 as line border , 2,3 as dash border
            _wordDoc.Content.Tables[n].Borders.Enable = use ? 1 : 2;
        }
        /// <summary>
        /// add row
        /// </summary>
        /// <param name="n"></param>
        public void AddRow(int n)
        {
            object missing = System.Reflection.Missing.Value;
            _wordDoc.Content.Tables[n].Rows.Add(ref missing);
        }
        /// <summary>
        /// add rows
        /// </summary>
        /// <param name="n">table number</param>
        /// <param name="rows">add rows count</param>
        public void AddRow(int n, int rows)
        {
            object missing = System.Reflection.Missing.Value;
            Table table = _wordDoc.Content.Tables[n];
            for (int i = 0; i < rows; i++)
            {
                table.Rows.Add(ref missing);
            }
        }
        /// <summary>
        /// Insert value to cell 
        /// </summary>
        /// <param name="table">target table</param>
        /// <param name="row">locate row</param>
        /// <param name="column">locate column</param>
        /// <param name="value">value</param>
        public void InsertCell(Table table, int row, int column, string value)
        {
            table.Cell(row, column).Range.Text = value;
        }
        /// <summary>
        /// Insert value to cell
        /// </summary>
        /// <param name="n">table number</param>
        /// <param name="row">locate row</param>
        /// <param name="column">locate column</param>
        /// <param name="value">value</param>
        public void InsertCell(int n, int row, int column, string value)
        {
            _wordDoc.Tables[n].Cell(row, column).Range.Text = value;
        }
        /// <summary>
        /// Insert value to cell
        /// </summary>
        /// <param name="n">table number</param>
        /// <param name="row">locate row</param>
        /// <param name="columns">locate column</param>
        /// <param name="values">value array</param>
        public void InsertCell(int n, int row, int columns, string[] values)
        {
            Table table = _wordDoc.Content.Tables[n];
            for (int i = 0; i < columns; i++)
            {
                table.Cell(row, columns).Range.Text = values[i];
            }
        }
        /// <summary>
        /// Insert Picture
        /// </summary>
        /// <param name="bookMark">target bookMark</param>
        /// <param name="picturePath">picture path</param>
        /// <param name="width">picture width</param>
        /// <param name="height">picture height</param>
        public void InsertPicture(string bookMark, string picturePath, float width, float height)
        {
            object missing = System.Reflection.Missing.Value;
            object toStart = bookMark;
            object linkToFile = false;//the picture is link
            object saveWithDocument = true; // save with document
            object range = _wordDoc.Bookmarks.get_Item(ref toStart).Range;//insert picture locate
            _wordDoc.InlineShapes.AddPicture(picturePath, ref linkToFile, ref saveWithDocument, ref range);
            _wordDoc.Application.ActiveDocument.InlineShapes[1].Width = width;//set picture width
            _wordDoc.Application.ActiveDocument.InlineShapes[1].Height = height;//set picture height
        }
        /// <summary>
        /// Insert Text
        /// </summary>
        /// <param name="bookMark">target bookMark</param>
        /// <param name="text">value</param>
        public void InsertText(string bookMark, string text)
        {
            object toStart = bookMark;
            object range = _wordDoc.Bookmarks.get_Item(ref toStart).Range;
            Paragraph wp = _wordDoc.Content.Paragraphs.Add(ref range);
            wp.Format.SpaceBefore = 6;
            wp.Range.Text = text;
            wp.Format.SpaceAfter = 24;
            wp.Range.InsertParagraphAfter();
            _wordDoc.Paragraphs.Last.Range.Text = "\n";
        }
        /// <summary>
        /// kill word process
        /// </summary>
        public void KillWinWordProcess()
        {
            System.Diagnostics.Process[] processes = System.Diagnostics.Process.GetProcessesByName("WINWORD");
            foreach (Process process in processes)
            {
                var b = process.MainWindowTitle == "";
                if (b)
                {
                    process.Kill();
                }
            }
        }
    }
    
   
}

// program.cs
namespace export_doc
{
    internal class Program
    {
        public static void Main(string[] args)
        {
            Report report = new Report();
            report.CreateNewDocument(@"xxxxx.docx");
            report.InsertValue("warning_level", "Ⅱ");
            
            report.SaveDocument(@"xxxx.docx");
        }
    }
}