1996 Pontiac Bonneville my power windows wont work or my lo

I never had a problem then I came out from work 2 days ago to start my car after work and I had a hard time starting it. I finally got it started and back it out and it stalled again and couldn't get it started again, we get it towed to my brother in law's house and now the electrical has a problem too the power windows won't work the power locks wont wont work the trunk release wont work but all my lights work we changed the battery and the fuel pump the fuel pump relay and it still does not work please give me a suggestion I'm out of them myself