Theft deterrent system light is on and my truck won’t start.

Hello, as your 2020 vehicle is likely still underneath the terms of the factory warranty, I would recommend first visiting your local Chevrolet dealership for assistance. If for some reason you have an abnormal amount of mileage that has you over 36,000 miles already, I would recommend that you seek the guidance of a local repair shop near you. To me, it sounds like an electrical power problem. possibly starting from the battery. Hands on testing is needed. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops