I got a 1996 buick century with a 3:1 and its leaking anti freeze some were on the driver side of the motor and i dont no what it is to i can fix it. It didnt leak till it got warm out so i was thinking it was the thermostat but tell me what you think please

If the antifreeze is leaking out behind the exhaust manifold then i would say you have a freeze plug leaking . The plug is located on the sides of the engine block. They can be a real job to get out and replace. If you see the leak in the location i described then i would take it to a repair shop for repairs. Have them to inspect all the freeze plugs for damage. Hope this will help you.