Help with Secure Boot for Windows 11 switch

###Troubleshooting Help:

PC PARTS LIST

According to the Windows 11 requirements, all I need to do is replace my procesor and enable Secure Boot. I'm in the process of choosing a CPU, but I figured in the meantime, I can enable Secure Boot, right? However, it's been a pain and after countless videos and articles I still can't figure out what's wrong with my specific settings.

System info says I'm in BIOS Mode "Legacy" and guides I've seen say it should be in UEFI but perhaps my motherboard doesn't support that?

But in the Secure Boot page in BIOS, it says "Secure Boot State" - User, and OS Type is Windows UEFI Mode.

SEE BIOS PICTURES HERE

Full disclosure, my friend built this PC in early 2018 and gifted it to me, so I'm not the most savvy on it or its makeup. I would love and appreciate any assistance. I've gotten extended security prtection enabled through October of next year at least, but I would like this headache to be over and to be on Windows 11 finally, wihout having to shell out for a new computer since this one works perfectly fine for my needs.

Thank you.