Adding a macro?

[sodowarts]

First off, I'm a relative newbie. I found this macro(?) below and would like to add it to a worksheet because it is supposed to make it possible for me to highlight different words. To customize it to my needs:
1. where in the string do I add the words that I want highlighted
2. does it matter if I want to only highlight in one column
3. once customized how do I make it work on my worksheet.

Option Explicit
Sub HighlightCells()
    Dim Lookin As Range, ff As String
    Dim i As Long
    Dim Fnd As Variant
    Dim fCell As Range
    Dim ws As Worksheet
    Dim xitem As Variant
    
   ' Fnd = Array("default", "Google")
 Fnd = Array("Ad hoc", "Adaptable", "Adequate", "And/or", "Approximately", "As a minimum", "As applicable" _
     , "As appropriate", "As possible")

    For Each ws In Worksheets
        With ws
            For Each xitem In Fnd
                Set Lookin = .Cells.Find(xitem, Lookin:=xlValues, LookAt:=xlPart)
                If Not Lookin Is Nothing Then
                    ff = Lookin.Address
                    Do
                       Lookin.Characters(InStr(1, Lookin, xitem), Len(xitem)).Font.ColorIndex = 3
                        Set Lookin = .Cells.FindNext(Lookin)
                    Loop Until ff = Lookin.Address
                End If
                Set Lookin = Nothing
            Next
        End With
    Next

End Sub

Many thanks!