If User clicks a cell then expand that column

Hi

I need a event sub where if a user clicks on a cell that has data validation the column expands so the user can see the full description.

the code i already have for the sheet which after a user enters or changes anything then reapplies the data validation is this:

Private Sub Worksheet_Change(ByVal Target As Range)
'auto fills cells within selected range with the data validation rules

Dim Rw As Long
Dim val As Variant
If Intersect(Target, Cells) Is Nothing Then Exit Sub
Application.ScreenUpdating = False
'Need to change range to cover the area
Range("d5:cp200").Select

With Selection.Validation
.Delete
        .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _
        xlBetween, Formula1:="=Code"
        .IgnoreBlank = True
        .InCellDropdown = True
        
        .InputTitle = ""
        .ErrorTitle = ""
        .InputMessage = ""
        .ErrorMessage = ""
        .ShowInput = True
        .ShowError = True
Range("a1").Select

Application.ScreenUpdating = True
End With
    
End Sub

any ideas if this is possible?