Loading bar but volume/brightness/keyboard brightness works.

Hey my Mac crashed. I booted and the graphics acceleration wasn’t working. I rebooted with a PRAM and then it was stuck on a loading bar. I rebooted with shift key and managed to revert patches. Rebooted again with shift key and patched. Rebooted again and now it’s stuck on the loading bar which gets very far and the volume/brightness/keyboard brightness works but it won’t get passed this.

I have a usb key which is the same version as installed but it’s complaining about ‘downgrading’. Pretty sure I’m on 14.4.1 with 1.4.3.