Change Color of cell based on specific letter / text

Can anyone give VBA help on creating a macro?

To search the entire sheet and if any cell contains just an "A" turn the cell green. If it contains just an "R" turn the cell red.

If the cells contain anything thing else, do nothing.
For example "AM" then no change.

I can do this is conditional formatting, but I need a macro for it.

Hi

This could be simplified by making a loop to find A and color then find R and color using a subroutine.

But thats a job for you.

Enjoy

Sub GreenRed()

Dim rngFind As Range
    Dim strValueToPick As String
    Dim rngPicked As Range
    Dim rngLook As Range
    Dim strFirstAddress As String
    

    Cells.Select
    
    Set rngLook = Selection
    strValueToPick = "R"
    With rngLook
        Set rngFind = .Find(strValueToPick, .Cells(1, 1), LookIn:=xlValues, lookat:=xlWhole)
        If Not rngFind Is Nothing Then
            strFirstAddress = rngFind.Address
            Set rngPicked = rngFind
            Do
                Set rngPicked = Union(rngPicked, rngFind)
                Set rngFind = .FindNext(rngFind)
            Loop While Not rngFind Is Nothing And rngFind.Address <> strFirstAddress
        End If
    End With
    
    If Not rngPicked Is Nothing Then
        rngPicked.Select


    With Selection.Interior
        .Pattern = xlSolid
        .PatternColorIndex = xlAutomatic
        .Color = 255
        .TintAndShade = 0
        .PatternTintAndShade = 0
    End With
    End If
    
    Cells.Select
    
    Set rngLook = Selection
    strValueToPick = "A"
    With rngLook
        Set rngFind = .Find(strValueToPick, .Cells(1, 1), LookIn:=xlValues, lookat:=xlWhole)
        If Not rngFind Is Nothing Then
            strFirstAddress = rngFind.Address
            Set rngPicked = rngFind
            Do
                Set rngPicked = Union(rngPicked, rngFind)
                Set rngFind = .FindNext(rngFind)
            Loop While Not rngFind Is Nothing And rngFind.Address <> strFirstAddress
        End If
    End With
    
    If Not rngPicked Is Nothing Then
        rngPicked.Select
        
    With Selection.Interior
        .Pattern = xlSolid
        .PatternColorIndex = xlAutomatic
        .Color = 65280
        .TintAndShade = 0
        .PatternTintAndShade = 0
    End With
End If

End Sub