you can try to use the event
if you go to VBE
and click on your sheet
there you can try code
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
'prevent Select event triggering again
Application.EnableEvents = False
'ensure that only one cell is selected
If (Target.Count = 1) Then
'ensure that cell selected is from range A1:A10
If (Not Intersect(Target, Range(Cells(1, "a"), Cells(10, "A"))) Is Nothing) Then
'put current date and time
Target = Now
End If
End If
'enable the event again
Application.EnableEvents = True
End Sub
target.offset(0,1) = now