Sheet name from cell values

I have a code that takes date from "A7" and text from "G7" to name sheet. Sometimes however sheet names can be too long. How do I modify below code to get date and only the first letter of each word to form sheet name? So if "A7" is 9/24/23 and "G7" is "Georgia Network Meeting", then sheet name should be "Sep23-GNM".

Private Sub Worksheet_Change(ByVal Target As Range)
If Not Intersect(Target, Range("A7")) Is Nothing Then

    If Range("A7") = Empty Then
        ActiveSheet.Name = "Event" & ActiveSheet.Index - 1
    Else
        ActiveSheet.Name = Format(Range("A7").Value, ("mmmd")) & "-" & Range("G7")
        End If
End If

The message box output is perfect but how can it be modified to change sheet name as in my original code?

I ran into Compile error: Sub or Function not defined highlighted on "FirstLetters".............

You probably need to keep the Function FirstLetters from post #2

I am a novice to VBA. Can you please put both those together to show me how it works? I continue to get Compile errors!

YES! Thank you!