Either your coolant level is too low, or your cooling system components (water pump, thermostat, rad cap, hoses, etc) are failing. Under normal conditions you really should not be losing coolant, so if you have to continually add coolant there is cause for concern. Best to take it to a shop and have them look at it if you are unfamiliar with the system.
put on ac in car and over heats
Yes, on most cars it will.
Either 2 things...it breaks down...or it explodes
Need to change your thermastat i have done that but still over heats when driving
crack the engine block and oil mixes with water or antifreeze.
Need to change your thermastat i have done that but still over heats when driving
clogged radiator
It is radiation. Sunlight enters the car and heats up material inside.
Check coolant level Perhaps thermostat is not opening to allow coolant flow
Take the thermostat out, start the car and let it idle, see if it over heats. With the thermostat out of your car, it should just constantly circulate water, making it take longer to heat up. If it heats up fast then chances are that your pump is out. DO NOT LET THE CAR REDLINE.
Sounds like you need a radiator coolant flush or you need a bigger radiator for your vehicular transport thingy.
if your car over heats alot then that is a pretty good sign. aslong as it isn't your water pump. but thermostat is a good place to start. if you replace the thermostat and it still over heats. (assuming that is why you are asking) then it could be the water pump.