The setting to set the order of the boot devices is something else. It’s normally pretty easy to find, so if you don’t see it you probably don’t have it.
It’s possible the Windows boot file has been damaged. Actually, something kind of similar happened just a couple days ago in this thread: Garuda renamed my hard drive in UEFI after install and now can't boot it - #28 by flamming_python. In that topic, after running the installer in UEFI mode the boot file on the BIOS-mode Windows disk was damaged.
The solution ended up being to use Hiren’s Boot to get a live “rescue media” environment, then run some of the repair tools to restore the boot file.