02 cavalier over heating

a totally stuck thermostat closed, stopping flow thru rad. will do this the only cooling you have is the heater ,so turn it up to super high , to help but still driving it will warp the heads from to much heat after a while

Replace the thermostat and also make sure that there is enough antifreeze to get to the top of the motor aka heads 1 on a four cylinder two on a v6/v8. Go to you tube and learn what to do and how... You overlooking for a bleeder valve in your engine. Let the air out until the anti freeze show then lock it down. And your reserve always e you l d have water aka antifreeze. But then maybe it's to late if you melted it...and the engine. It's called basic car maintenance 101.

what does your exhaust look like ? , look under the oil fill cap what so you see ?

Actually when was the last time you checked the oil dipstick for the correct amount of oil some say 710 cover is where you add oil if needed. The oil stick tells you how much you need to add if any.. depends oh on quality and engineers expediency...

Maybe no fan belt too

Should be simply a bad thermostat , also I haven't used water in my radiator for at least 40 years , I just add Anti Freeze !!