96 cavalier starter/ignition

My '96 cavalier has a starter problem, or at least it was the starter, my boyfriend put a new starter in my car but now you cannot start it in the car when you put the key in the ignition, so I have been starting it with a screw driver. Then my ghetto rigging boyfriend decided he was going to hook up a push button to the inside of the car so i didn't have to keep getting out to start it with the screw driver, and now it doesn't start at all. Well it turns over it just wont start, and I'm sick of listening to him about what the problem COULD be and was wondering...what the hell I do with it. I don't have much money but I need to find out the real problem. Could it be the ignition? Still the starter? Or the computer?