Q: My car won’t start the engine and oil light was on

So I was driving my car and the engine started to make a loud rattling sound only when I first started it up and when I would accurate. I took it to the mechanic and he said that I needed to get oil, coolent and some stop leak for the oil. Mind you I got my oil changed 2 week prior to the mechanic checking it. He said the oil was burning out thru the exhaust. So I did that and put everything In. My car still was making the rattling sound in the front. I drove it to work and on my way back my car stopped and steering wheel locked up but my light and everything stayed on. I turned the car of and it started back up, I did that like 4 times before I made it home. I let the car sit all day today and when I got back home and try to start it up all it does is rapid clicking. The light and radio still come on and the light in the car are not dim. No-start, no-turn over. Can someone please tell me what’s going on