Try something like the following:

Sub AAA()

   Dim LastRow As Long
   Dim FirstRow As Long
   Dim RowNdx As Long
   Dim WS As Worksheet

   FirstRow = 1 '<<< CHANGE AS REQUIRED
   Set WS = Worksheets("Sheet1") '<<< CHANGE AS REQUIRED

   With WS
       LastRow = .Cells(.Rows.Count, "A").End(xlUp).Row
       For RowNdx = LastRow To FirstRow Step -1
           Select Case Left(.Cells(RowNdx, "A").Value, 2)
               Case "FC", "PB", "GR"
                   .Rows(RowNdx).Delete shift:=xlUp
               Case Else
                   ' do nothing
           End Select
       Next RowNdx
   End With

End Sub