Ah so a full protection of the sheets but allow the buttons to do their work , and only the admin knows the password.
Put below in a fresh module and play it and protect your VBAProject with same or different password.

Sub protecteverything()
Dim wSheet As Worksheet
    For Each wSheet In Worksheets
        wSheet.Protect Password:="AZERTY987654321", _
        UserInterFaceOnly:=True
Next wSheet
MsgBox "sheets protected "
End Sub