2021 CADILLAC CT5 Unknown Or Other Problems

While driving on a very busy highway going downhill when suddenly the vehicle started feeling abnormal like it was going to turn off automatically, heard an abnormal grinding noise coming from the engine the vehicle dropped speed drastically and the check engine light turned on , luckily we were on a part of the road where I merged quickly to the side of the road followed by a sudden engine shut down, the safety of myself and 3 other passengers was very compromised due to nearly being hit by other vehicles coming at a high speed on a main highway when my vehicle suddenly slowed down coming to a shut down due to the engine failure, I attempted to turn the car on again but would not turn on, was not getting any response at all, had to get the car towed, the vehicle did not have other warning lights...

Driver Side door handle stops working. Because the door handle operates with a sensor and not a standard pull door handle something is being affected and it will not open door. Causing safety issue and not being able to enter car normally.