Loud exhaust leak+coolant leak+overheating

What is your question?

I've only owned my car for 5 months. I havent even put 1000 miles on it yet. It already had a loud exhaust leak. It overheated last month and that's when I noticed that the coolant was rusty colored. I put new coolant in it. But it started to leak, and not on the ground. It still tries to overheat and the rust color has gotten even darker. Could this be from the exhaust leak? I don't know if the lower intake manifold gasket was replaced before I got the car. Also, I'm going to have to change the oil after less than 1000 miles because my oil has become extremely sooty, even though I put synthetic in it. 2 weeks ago it started to become sluggish, and no matter how far I pushed the gas petal, it wouldn't go above 30 mph. That stopped after a few days of not driving it. My check engine light has been on for a while but has gone off twice in the past few days.