Welcome to the forum
You need to read the diagnostic codes to know what is going on…
You can buy a cheap
obd2 bluetooth diagnostic scanner off eBay. They range in price from $15 and up. Jaycar has them for $70. Then install an app on your phone, plug the scanner into the OBD port near drivers right knew and read the engine codes would be the first step…
Or if you have a spare laptop and aren’t a Neanderthal with tech, buy a
VXDiag Nano for GM and then you can do a lot more; as much as the dealer with GM subscription
Read
this thread fully…
If you don’t want to buy a code scanner, Supercheap offers a service to read the codes. No idea what or if they charge for this service…
Then come back here and with all current and historic codes and some may be able to help
Otherwise you’ll need to take it to a mechanic/dealer
PS: if you click on the blue text, it’s a hyperlink and will take you to other magical places