Sub TestX()
    Dim rng As Range
    Dim cel As Range

    'Worksheets("Лист1").Cells.Select

    Set rng = Selection

    Range("A1") = "Количество красных ячеек:"
    Range("A2") = "Количество синих ячеек:"
    Range("A3") = "Остальные цвета:"

    Range("B1") =  0 
    Range("B2") =  0 
    Range("B3") =  0 

    For Each cel In rng
        Select Case cel.Interior.ColorIndex
            Case  3 
                Range("B1") = Range("B1") +  1 
            Case  5 
                Range("B2") = Range("B2") +  1 
            Case Is <> xlNone
                Range("B3") = Range("B3") +  1 
        End Select
    Next cel
End Sub