Show Userform on Cell Select

Hello,

I have a sheet that inserts data into the next blank row. the offset 4 value is a date.

Can i have it so when i click the date on this sheet it shows the userform.

what i cant get is how to do it since i dont know what row the date will be in.

I tryed

Private Sub Worksheet_SelectionChange(ByVal Target As Range)
If Target.Colum = 4 And ActiveCell <> "" Then
    Cancel = True
    frmCalendar.Show
End If
End Sub