How to get off the door panel to check on electrical things in 95 Camaro Z-28

I just purchased a 1995 Z-28 Cpe V-8 Automatic for my grandson. I'm having problems with the key working in the doors. The key does work in the trunk though. He can open the doors with the remote as well, but not locking the doors. Also the electric window switch doesn't work all the time. So I thought, if I can take off the door panel, and start replacing things in there I would eventually fix what is causing the problems.....Many many thanks in advance for any advise.....Opa Peter