As for the low oil pressure, most likely the oil pressure sending unit needs to be replaced as it is a common failure part.

An Engine Requires 10 psi of oil pressure for every 1,000 rpm. so at idle, it does not require much,,, at 3,000 rpm, the engine requires 30 psi. You can install an actual pressure tester at the sending unit port if you would like to see actual numbers for diagnosing.

Replacing the sending unit will most likely take care of the oil pressure issue.

I some cases the check engine light can be set with a “check Gauges”. But it is a good idea to check the codes and proceed once you have the actual codes.