Insert A Blank Column Next To Heading Columns

I am doing a lookup, populating a column (which works although slowly) then (in this part) doing a search on the header row.. If the heading contains the word "Category", I wish to insert a blank column next to (the column containing the heading), colour it yellow then look for the next heading and repeat if found.

It appears to clear my first row so I must have my columns referred incorrectly as rows

Dim FWord As String
Dim i As Integer
Dim lCol As Long
Dim MyString As String
.
.
FWord = "Category"
lCol = Range("A1").End(xlToRight).Column
For i = 1 To lCol
Cells(1, i).Value = MyString '