Sheet name from cell values

Something like this will work

Sub abc()
 MsgBox Format(Range("a7").Value, ("mmmd")) & "-" & FirstLetters(Range("g7").Value)
End Sub
Function FirstLetters(str As String)
    Dim words As Variant
    Dim resultStr As String
    Dim i As Integer

    words = Split(str)
    For i = 0 To UBound(words)
        resultStr = resultStr & Left(words(i), 1)
    Next i

    FirstLetters = UCase(resultStr)
End Function