my engine gets extremely hot and starts smoking, but there is coolant and the radiator fan works. There's also oil in the engine. I'm not sure what's going on. Also, when I drive the car and I try to accelerate it makes a loud rattling noise. The noise stops when I take my foot off the gas.

 

What color does it smoke? Also check the coolant for any air pockets.

 

Check for air in coolant (or change it completely if you don't know the last time it's been done...)

Your Thermostat could be bad, which would stop coolant from circulating.

What kind of rattling sound? Can you find the sound on YouTube, or take a video? It may or may not be related, but it's practically impossible to know without hearing the sound.

 

Any coolant loss in radiator or reservoir?
How long does it take to overheat from a cold start (sitting overnight)?
Put a large piece of cardboard under engine/transmission and run engine with heater on max hot temp, fan on 4. Look for coolant/water on cardboard.

Overheating could be due to any one or combination of the following:
Thermostat stuck closed
Waterpump partially or fully failed
Air in coolant
Blown head gasket
Clogged radiator