Check engine light on

A check engine light can be triggered by a myriad of things so that's why it's most important to have a mechanic or auto parts store use their scan tool to find the trouble codes. They then will have a reference that will tell them (and you) what the problem(s) is.

Most auto parts stores will provide this service for free. I would have this done right away so as to minimize the risk of doing damage to the vehicle from continued use.

Lots of different minor things could cause the check engine light to come on , even something as simple as a loose gas cap.
Most mechanics can plug in a diagnostic tool that will read a code from your computer that will tell them what is causing the light to come on.
This should not be an expensive test.