2001 Ford Expedition - Power loss & loud clunk noise. What wrong?

I have a 2001 Ford Expedition & yesterday I was driving it when I came to a stop. The vehicle starting shaking a bit & rpms dropped and the car shut down. I tried restarting it but it would sometimes act like it was going to turn on but then turn off again. On one attempt I finally got it to run again but I got stuck on a red light on the next street and again it started shaking and the car shut off. After multiple attempts it finally turned back on but was lacking so much power. I was pushing the accelerator and It would barely walk. As I was crossing the light and making a left turn this loud and I mean LOUD clacking or breaking noise appeared to be coming front the front left tire a few moments later when I stopped turning the steering wheel and drove straight the suv got power again. I parked in a emptying lot and waitied. About 2 hours later it worked perfectly so I drove home. When I got home and parked it I turned it off and tried restarting it and it didn't start and the loud noise appeared once again. Please help I don't know what's wrong with it, I asked a local mechanic and he didn't really know.

Lol

You need a mechanic, not a forum. Surgery, not medicine.

Check for spark. Check if the injectors are firing and getting command to fire. Check fuel pressure. Disconnect the PCV line, spray brake parts cleaner on the line, reconnect the line and try to start. If it starts then stalls after a few seconds, check for a bad fuel pump. The loud noise will need to be diagnosed by another mechanic.

Might be the AC compressor is locking up or seizing? This can throw the serpentine belt, break the serpentine belt, or make horrible noises while the engine is trying to turn the AC compressor pulley and the belt is dragging. Try NOT using the AC or defroster when this noise appears to see if that makes it go away. Have someone look at the underside of the engine and at the suspension parts.