You can create a program (often referred to as a macro or script) to automate repetitive copy-paste tasks between Microsoft Excel and Word. One of the most common ways to do this is by using VBA (Visual Basic for Applications), which is integrated into both Excel and Word.

Steps:

1. Prepare Your Excel Worksheet and Word Document:
   • Have your Excel file (Source.xlsx) and Word document (Target.docx) ready.
   • In this example, we’ll be copying from the first cell (A1) of the Excel file to the start of the Word document.
2. Open the Excel File and Access the VBA Editor:
   • Press Alt + F11 to open the VBA editor in Excel.
3. Insert a New Module:
   • In the VBA editor, right-click on “VBAProject (Source.xlsx)” > Insert > Module.
4. Enter the VBA Code:
   • In the module window, paste the following VBA code:

   Sub CopyFromExcelToWord()
   
       ' Define variables for Excel and Word objects
       Dim wb As Excel.Workbook
       Dim ws As Excel.Worksheet
       Dim wdApp As Object
       Dim wdDoc As Object
   
       ' Set references to the active workbook and worksheet
       Set wb = ThisWorkbook
       Set ws = wb.Sheets("Sheet1")
   
       ' Start Word application and open the target document
       Set wdApp = CreateObject("Word.Application")
       wdApp.Visible = True
       Set wdDoc = wdApp.Documents.Open("C:\path\to\Target.docx")
   
       ' Copy the value from A1 of the Excel worksheet
       ws.Range("A1").Copy
   
       ' Paste the copied value to the start of the Word document
       wdDoc.Content.InsertBefore ws.Range("A1").Value
   
       ' Save and close the Word document
       wdDoc.Save
       wdDoc.Close
   
       ' Clean up objects
       Set wdDoc = Nothing
       Set wdApp = Nothing
       Set ws = Nothing
       Set wb = Nothing
   
   End Sub
           

   Note: Make sure to replace “C:\path\to\Target.docx” with the correct path to your Word Document.

5. Run the Macro:
   • Close the VBA editor.
   • In Excel, press Alt + F8, select CopyFromExcelToWord, and click “Run”.
6. Review the Word Document:
   • Open Target.docx and you should see the value from A1 of your Excel file at the start of the document.

Remember:

• Always backup your files before running macros.
• Adjust the cell references and document paths as needed to match your specific use case.
• This is a basic example. Depending on the complexity of your task (e.g., formatting, multiple cells, tables), the VBA code may need further customization.