A little background, my laptop suddenly crashed one day and it would not start windows, it would simply get past the Dell logo and then the screen would stay black until shutdown.
After a couple of times of this it would show recovery options for windows, atfer choosing to restore windows while preserving user files and waiting for it to complete it would now show a blue screen with a BCD error.
Now the next step would be to use a recovery media to repair windows start or simply reinstall it, problem is I can't get it to start from the usb.
As mentioned in the title I cannot disable secure boot, I can set it to disable and apply the changes, but then if I go to boot options I can't change from UEFI to legacy or I get an error(Need to disable SecureBoot) which is already done. So I restart hoping I can choose Legacy now but again the same error shows and Secure Boot shows enabled. Other BIOS settings also reset after every restart, the clock however does not.
I tried updating the bios, using F12 for the boot menu there is an option to update the bios, I then select the file from the usb which is correctly recognized and the process starts and it completes almost immediately but upon restart the bios version is still the same 1.0.
I have tried leaving UEFI, going into Boot Sequence and Add Boot Option selecting the usb which is recognized correctly but upon saving, restarting and using F12 I can't see the option I added for the USB. I'm using similar steps to the ones here starting at step 3: 
I used rufus to create the usb.
Apart from using an actual dvd which I still don't think it would work I'm not sure what else to do. Any ideas?
I tried to provide as much information as I could, let me know if you would like me to check something else.