If your Windows PC is stuck in a boot loop after the BIOS update, perform a hard reset. This article lists some effective fixes for this issue.

Boot failure is a common issue that prevents proper PC startup. It can result from hardware malfunctions, corrupted system files, or boot configuration issues in Windows 11.

I was also able to boot to a GRUB setup on my flash drive, but I wasn't able to get the Windows 7 installation to start with that either, mostly because I have no idea how it works.