Readings and signals "low oil pressure", "engine power reduced stop engine"

I purchased the car and the ride home no displays were on, however I didn't try to drive again until I got my plates. I probably drove for 15 minutes before dash started reading "low oil pressure", "engine power reduced stop engine". I then stopped at nearest store and went in came out it started but seconds later shut off I tried to start it and it started reading "starting disabled service throttle". I just recently replaced the oil pressure sensor do I haven't seen the low oil pressure pop up again. But, it won't start still and I still see readings for "engine power reduced" and "starting disabled service throttle". What should my next steps be and what exactly could be causing this issue? Google is giving me so many different answers and has utterly confused me.