add an addition cell colour to coding

[p45cal]

Since there is only one colour, you don't need to set up arrays, nor colour the cells one by one, and if you want to add more colours later a select case construct is easier to add to:

Sub shadeCells(rangeToShade As Range, Target_Name As String)
Dim myColor As Long
Select Case True
  Case UCase(Left(Target_Name, 6)) = "N-SIDE": myColor = 65535
  Case UCase(Left(Target_Name, 3)) = "ADD": myColor = 13353215
  'Case UCase(Left(Target_Name, 14)) = "SOMETHING ELSE": myColor = 9999' add more if you want.
  Case Else: myColor = 4050606
End Select
rangeToShade.Resize(, 9).Interior.Color = myColor
End Sub