won't start 98 buick regal on 1998 Buick Regal

i left my sons school and the car was running fine i told him to turn on the air and when he hit the a/c button the car shut off and will not start back up.I had to get it towed to my house and when you turn the key you will hear 1 click and that's all

Asked by for the 1998 Buick Regal
The a/c compressor may be damaged keeping the engine from turning. Try removing the serpentine belte and see if the engine will turn over. Just don't run the engine to long with the belt off. It will overheat because the water pump is not turning.
1 more answer , 1 more comment
it wont turn engine over need more information a/c pully would have to freeze up it shood turn free with compressor power off
at the school it started fine and when we pulled out on the road i told him to turn the a/c on and when he hit the button it shut off had no power.My wife came and i tried to jump it off cause it was acting like the battery was dead but it would not do anything but make a loud click or thump .When you turn the key all the dash lights come on just wont do anything else.Thanks for your help