No signal after attempting to update BIOS need help diagnosing

I was troubleshooting a Riot Vanguard anti-cheat error (VAN9005) with Claude, who told me to make sure Secure Boot and TPM were correct in the BIOS.

Went into BIOS to enable Secure Boot, it said System in Setup Mode, stating the following:

which led into Key Management where I attempted to update the PK key. Doing this required me going into custom key mode instead of the preset whatever, then saved and exited.

PC then failed to boot, black screen, no signal, just idle. Tried re-entering BIOS but couldn't get in.

From there I looked up the issue and removed the CMOS battery, left it out for some 20 minutes and placed it back. When turning my computer on again, it began a boot loop of some sort. Fan on, lights on, for ~10s then off and repeats ~4 times, before my keyboard lights turn on and the boot-loop stops. I could not enter the BIOS screen so I figured I had done something wrong and repeated the process, resulting the same exact.

Looking for any info on how to restore the old BIOS settings or if it's a different issue entirely. Happy to answer any and all questions I can but this is well outside my expertise.

Specs:

• CPU: Intel i5-10400F
• GPU: RTX 2070
• Motherboard: Gigabyte B560 HD3
• RAM: 48GB total (2x16GB 3200MHz + 2x8GB TeamGroup 2400MHz)
• Storage: WD Blue SN550 1TB NVMe (boot drive)
• OS: Windows 10 Home, 22H2