Try this:

Sub LMP_Test()

    Dim lngCountValues                  As Long
    Dim rngRangeToApplyMultiply         As Range
    Dim rngEachCell                     As Range

    Set rngRangeToApplyMultiply = Range("A1:M1")
    
    lngCountValues = 0
    For Each rngEachCell In rngRangeToApplyMultiply
        lngCountValues = lngCountValues + 1
        rngEachCell.Offset(lngCountValues).Value = rngEachCell ^ 2
    Next rngEachCell

End Sub