Hi, I have a button where I add a new column after a specific column. In my case H.
After adding one column, the user can add more columns, and these should be to he right of the last added column. 

Private Sub add_quantity_Click()
    ActiveSheet.Unprotect
    Columns("H:H").Insert
    
    Range("H5").Select
    Selection.Locked = True
  
    Range("H6").Select
    Selection.Locked = False
    
    Range("H7").Select
    Selection.Locked = False
    
    Range("H7").Select
    Selection.NumberFormat = "0.00"
   
    
    ActiveSheet.Range("H2").Select
    With ActiveSheet.Buttons.Add(Selection.Left, Selection.Top, Selection.Width, Selection.Height)
        .OnAction = "delete_quantity_click"
        .Characters.Text = "Delete"
    End With
    Application.ScreenUpdating = True
    ActiveWorkbook.Save
    ActiveSheet.Protect
End Sub
See attached pictures... 1, 2, and 3

1.png
2.png
3.png