AB350 Gaming K4 enable secure boot

I'm not a new member, but I suppose I still need to post here. =D

I have an ASRock AB350 Gaming K4 mobo, BIOS version 7.40. I'm running Window 10 Pro, 64-bit.

I am trying to enable Secure Boot (for BF6, if that has been a common theme lately lol). I have been following the following guides: https://help.ea.com/en/articles/technical-issues/secure-boot/ and https://www.asrock.com/support/faq.asp?id=531

System Summary shows my BIOS as Legacy and Secure Boot unsupported. When I try to view my C drive properties in Disk Management, there is no Volumes tab to determine if it is GPT or MBR, in regards to following the EA guide. Because of that, I believe I basically cannot take any further steps until I know if my partition style is GPT or MBR.

When following and completing the ASRock guide, my PC ended up in an endless loop of starting in BIOS mode. This stopped once I selected to Load UEFI BIOS Defaults in the Exit tab. I wasn't sure what exactly that'd do, maybe automatically change my BIOS from Legacy to UEFI, I hoped. But once Windows started, my System Summary still showed BIOS Legacy and Secure Boot unsupported.

So I ask, is it even possible for me to enable Secure Boot if I'm unable to determine what type of Windows disk partition style I have? The BIOS mentions "Secure Boot aware OS". Is it possibly my Windows install is not Secure Boot aware since it is a janky install? I believe my only reasonable option with the least troubleshooting is to just upgrade to Windows 11. But will my janky Windows 10 install somehow also make my Windows 11 install janky (or is that a MS Community question?), unless I do a clean Windows 11 install?

Thanks for any help or input!