What next

I got a 2011 Buick Enclave CXL. 2 weeks ago while driving it, the engine lost power (all other electronics in car had power). I turned off the car and restarted it for the engine to instantly die again. I was in between oil changes so I ended up adding 3 qts of oil to hold it over (apparently there was no oil in it). Car would start but the moment I was idling/waiting at lights/stop signs, the engine would die. I ended up just kept driving and barely stopping till I got it home.

The check engine light has came on but it was saying crankshaft and other error codes similar to the crankshaft. I recently cleaned the throttle body as that part was filthy and tried to reset it but the same issue keeps happening. What should I do next?