Car going backwards when in forward drive, radio, A/C not working and LED screen blank

There could be a network fault, which will shut down multiple modules. You will need to start with a scan, specifically a network test.

Here is a video that will show what specifically needs to be done:

https://www.youtube.com/watch?v=InIlnsjOVFA

The CAN network is basically the communication highway in which these modules communicate. When there is an issue, it will set codes but this can cause all sorts of different issues in the other systems on the vehicle.

This will explain this network a little more:

https://www.2carpros.com/articles/can-scan-controller-area-network-easy

Please take a look at these guides and then let me know if you have any codes and we can go from there. Thanks