More than one visual basic code

Private Sub Worksheet_Change(ByVal Target As Range)
    If Target.Value = "" Then
        Exit Sub
    Else
        Sheets("Sheet1").Unprotect Password:="bob"
        Target.Locked = True
        Sheets("Sheet1").Protect Password:="bob"
    End If
End Sub

    Private Sub Worksheet_Change(ByVal Target As Excel.Range)
        With Target
            If .Count > 1 Then Exit Sub
            If Not Intersect(Range("A2:A750"), .Cells) Is Nothing Then
                Application.EnableEvents = False
                If IsEmpty(.Value) Then
                    .Offset(0, -1).ClearContents
                Else
                    With .Offset(0, -1)
                        .NumberFormat = "ddd. dd mmm yy hh.mm"
                        .Value = Now
                    End With
                End If
                Application.EnableEvents = True
            End If
        End With
    End Sub

Sorry to keep making threads, but where do I put these two pieces of code so that they run smoothly alongside each other. The first code is so that only blank cells can be edited.

Could someone give me a step-by-step on what to click and so on, because I'm not at all sure how to use visual basic. The worksheet_deactivate doesn't appear to be working.