I am trying to Hide Columns based on a drop down list answer if it appears on any row

Hi arugg321,
welcome!
try this

Private Sub Worksheet_Change(ByVal Target As Range)
If Not Intersect(Target, Range("d11:d32")) Is Nothing And Target.Value = "Mileage" Then
Columns("h:k").EntireColumn.Hidden = False
Else
Columns("h:k").EntireColumn.Hidden = True
End If
End Sub

nb
next time when you post a code, please read the forum rules to know "how to"