Why wont my 1992 chevy caprice turn on or off and the key is out of the ignition?

i was driving my 92 chevy caprice when i turned it off got out of the car for a minute got back in put in in the start position because i have fuel injection i must wait til it stops beepin and the radio turns on to compleatly start it one i did and tried to start it i had no sound at all. it would not start! or turn off. i unplugged the battery and pluged it back up still nothing but it would not turn off i went and bought an ignition lock we instilled it by the directions it came with i must say it was very difficult and was shown on you tube a total other way to do it my steering wheel is sittin in my back seat because this still didnt work.... PLEASE i need help anyone