Use the Workbook_Open event. You go into the vbe and right click on the
thisworkbook entry in your project in the project explorer, selecting view
code. In the resulting module, select Workbook from the left dropdown at the
top and Open from the left one.
Private Sub Workbook_Open()
End Sub
Put your code in this procedure or call it from this procedure.
If you want to allow the user to make entries, lock all cells but the ones
where the entries will be made - those should be unlocked. Then protect the
sheet. for the sheet, set EnableSelection = xlUnlockedCells
But, this will allow the curor to be shown - you can't have it both ways.