Message box code

Hello,
I have a code already written to execute an operation in a selected sheet. (sheet 23)
I need help writing a code in a message box.
If I enter in column L (in sheet 23) the word "BAB", the code should show me the message box saying: "Are you sure about the information?" with 2 options below "YES" and "NO".
If I select yes, I want it to execute my code.
If I select no, I want it to only make the message box diasppear, without executing anything.
Thanks for your help.

Hi,

copy this to the Worksheet module of Sheet 23.

Private Sub Worksheet_Change(ByVal Target As Range)

Dim MyQ1 As String
If Not Target.Column = 12 Then Exit Sub
If Not Target.Value = "BAB" Then Exit Sub
MyQ1 = MsgBox("Are you sure about the information?", vbYesNo)
If MyQ1 = vbNo Then Exit Sub

'YOU CODE HERE
MsgBox "You clicked yes"
End Sub

Sorry if I didn't make myself clear enough.
The code I already have is activated when selecting "BAB" in any row of the column L

Private Sub Worksheet_Change(ByVal Target As Range)
    Dim myDestSheet As Worksheet
    Dim myDestSheet2 As Worksheet, destRow As Long, destRow2 As Long
    With ThisWorkbook
        If Target.Cells.Count = 1 And Target.Column = 12 And Target = "BAB" Then
            On Error Resume Next
            Set myDestSheet = Worksheets(Target.Offset(, -11).Value)

            If Err.Number = 9 Then
            On Error Resume Next
            Set myDestSheet2 = Worksheets(Target.Offset(, -10).Value)

                If Err.Number = 9 Then
                On Error Resume Next
                MsgBox "Sheet " & Target.Offset(, -11).Value & Chr(10) & " Does Not Exist " & Chr(10) & " NO DATA WAS ADDED "
                Err.Clear
                    MsgBox "Sheet " & Target.Offset(, -10).Value & Chr(10) & " Does Not Exist " & Chr(10) & " NO DATA WAS ADDED "
                    Err.Clear

                
                Else
                    destRow2 = myDestSheet2.Cells(Rows.Count, "a").End(xlUp).Row + 1
                    Application.EnableEvents = False
                    Target.Parent.Cells(Target.Row, 5).Resize(, 7).Copy .Sheets(myDestSheet2.Name).Cells(destRow2, 5)
                    With myDestSheet2
                        .Cells(destRow2, 1) = Target.Offset(, -9)
                        .Cells(destRow2, 2) = Target.Offset(, -8)
                        .Cells(destRow2, 3) = "SIC"
                        .Cells(destRow2, 4) = Target.Offset(, -11)
                    End With
                    Application.EnableEvents = True
                    MsgBox "Sheet " & Target.Offset(, -11).Value & Chr(10) & " Does Not Exist"
                Err.Clear
MsgBox " Data was added to Sheet " & Target.Offset(, -10).Value
Err.Clear
                End If
                    Else
                destRow = myDestSheet.Cells(Rows.Count, "a").End(xlUp).Row + 1
                Set myDestSheet2 = Worksheets(Target.Offset(, -10).Value)

                If Err.Number = 9 Then
                On Error Resume Next
                    Application.EnableEvents = False
                    Target.Parent.Cells(Target.Row, 5).Resize(, 7).Copy .Sheets(myDestSheet.Name).Cells(destRow, 5)
                    With myDestSheet
                        .Cells(destRow, 1) = Target.Offset(, -9)
                        .Cells(destRow, 2) = Target.Offset(, -8)
                        .Cells(destRow, 3) = "PIC"
                        .Cells(destRow, 4) = Target.Offset(, -10)
                    End With
                    Application.EnableEvents = True
                    MsgBox "Sheet " & Target.Offset(, -10).Value & Chr(10) & " Does Not Exist"
                    Err.Clear
MsgBox " Data was added to Sheet " & Target.Offset(, -11).Value
Err.Clear
                    Else
                    destRow2 = myDestSheet2.Cells(Rows.Count, "a").End(xlUp).Row + 1
                    Application.EnableEvents = False
                    Target.Parent.Cells(Target.Row, 5).Resize(, 7).Copy .Sheets(myDestSheet.Name).Cells(destRow, 5)
                    Target.Parent.Cells(Target.Row, 5).Resize(, 7).Copy .Sheets(myDestSheet2.Name).Cells(destRow2, 5)
                    With myDestSheet
                        .Cells(destRow, 1) = Target.Offset(, -9)
                        .Cells(destRow, 2) = Target.Offset(, -8)
                        .Cells(destRow, 3) = "PIC"
                        .Cells(destRow, 4) = Target.Offset(, -10)
                    End With
                    With myDestSheet2
                        .Cells(destRow2, 1) = Target.Offset(, -9)
                        .Cells(destRow2, 2) = Target.Offset(, -8)
                        .Cells(destRow2, 3) = "SIC"
                        .Cells(destRow2, 4) = Target.Offset(, -11)
                    End With
                    Application.EnableEvents = True
                End If
                End If
        End If
    End With
End Sub

What I need to do is to create a message box that appears when I select in column L the word "BAB" to let me confirm that the information entered are true. If I select Yes, I want it to execute the previous code, and if I select No, I want it to dismiss the message without doing anything so I can edit my information again.
Thanks

Private Sub Worksheet_Change(ByVal Target As Range)
    Dim myDestSheet As Worksheet
    Dim myDestSheet2 As Worksheet, destRow As Long, destRow2 As Long
    With ThisWorkbook
        If Target.Cells.Count = 1 And Target.Column = 12 And Target = "BAB" Then
            '''' NEW PART ''''
            Dim MyQ1 As String
            MyQ1 = MsgBox("Are you sure about the information?", vbYesNo)
            If MyQ1 = vbNo Then Exit Sub
            '''' END OF NEW PART ''''
            On Error Resume Next
            Set myDestSheet = Worksheets(Target.Offset(, -11).Value)

            If Err.Number = 9 Then
            On Error Resume Next
            Set myDestSheet2 = Worksheets(Target.Offset(, -10).Value)
        'etc etc etc rest of the code

Thanks alot, it works perfectly

When I select NO, the code execution stops, but the word in column L stays (BAB). How can I clear it?

            '''' NEW PART ''''
            Dim MyQ1 As String
            MyQ1 = MsgBox("Are you sure about the information?", vbYesNo)
            If MyQ1 = vbNo Then Target.Value = "": Exit Sub
            '''' END OF NEW PART ''''

Thank you for your help