I want to convert this code from spire.xls to normal excel.application using WPF

  public void myCodeSpire ()
{
           //excel File Destination
           workbook newBook = new Workbook();    
           newBook.LoadFromFile("ExcelFileDestination.xls", ExcelVersion.Version97to2003);
           Worksheet newSheet = newBook.Worksheets[0];
           //excel File Source
           Workbook workbook = new Workbook();   
           workbook.LoadFromFile(ExcelFileSource.xls, ExcelVersion.Version97to2003);
           Worksheet sheet = workbook.Worksheets[2];


        foreach (CellRange range in sheet.Columns[0])
              {
                if (range.Text == KeySearch)
                  {
          CellRange sourceRange = sheet.Range[range.Row, 5, range.Row + 2, 7];
          CellRange destRange = newSheet.Range[34, 3, 36, 5];
          sheet.Copy(sourceRange, destRange,true);


          sourceRange = sheet.Range[range.Row, 9, range.Row + 2, 11];
          destRange = newSheet.Range[34, 6, 36, 8];
          sheet.Copy(sourceRange, destRange, true);
                   

           sourceRange = sheet.Range[range.Row, 13, range.Row + 2, 13];
           destRange = newSheet.Range[34, 9, 36, 9];
           sheet.Copy(sourceRange, destRange, true);

                 
            sourceRange = sheet.Range[range.Row, 15, range.Row + 2, 15];
            destRange = newSheet.Range[34, 10, 36, 10];
             sheet.Copy(sourceRange, destRange, true);

                  
                   }
              }

      newSheet.Range["C34:J36"].NumberFormat = "0.000";
      newSheet.Range["C34:J36"].Borders.LineStyle = LineStyleType.Thin;
      newSheet.Range["C34:J36"].Borders.Color =System.Drawing.Color.Black; 

      newSheet.Range["C34:J36"].Border[BordersLineType.DiagonalDown].LineStyle= LineStyleType.None;

      newSheet.Range["C34:J36"].Borders[BordersLineType.DiagonalUp].LineStyle = LineStyleType.None;
      

       
 newBook.SaveToFile("ExcelFileDestination.xls", ExcelVersion.Version97to2003);
}

public void myCodeExcel.Appli()
{
 Excel.Application APP = new Microsoft.Office.Interop.Excel.Application();
        //Destination
 Microsoft.Office.Interop.Excel.Workbook newBook = APP.Workbooks.Open(excelFileDestinationPAth);

       Microsoft.Office.Interop.Excel.Worksheet newSheet = (Microsoft.Office.Interop.Excel.Worksheet) newBook.Worksheets[1];        
        
// source
    Microsoft.Office.Interop.Excel.Workbook workBook = APP.Workbooks.Open(excelFileSourcePAth);

       Microsoft.Office.Interop.Excel.Worksheet sheet = (Microsoft.Office.Interop.Excel.Worksheet) workbook.Worksheets[3];               
     foreach (CellRange range in sheet.Columns[0])
          {
              if (range.Text == KEYsearch)
              {
         
            //getdata search code from source and copy it in excel file destination


         }


newBook.save(excelFileDestinationPath);