Windows 10: Windows 10 can't login, reset/reinstall or access BIOS

I started having this problem at around 3PM today and I've been trying to fix it for the last 7 hours.
So basically, I can't log in at the lock screen. After entering my password it starts to load and then goes black for less than a second and I'm back at the lock screen. I'm pretty sure it's cause of my UX theme patcher theme that I installed a while ago, although I don't know why I only have this problem now, cause I've used that theme for at least a year or so.
This happened when I was changing some things in my PC, adding shortcuts to the desktop etc and I wanted to get rid of the arrow that shortcuts have so I edited the registry a bit, but soon changed it back to default. Then I used a program called 7+ taskbar tweaker to make my taskbar a bit thinner. Everything was working fine but I did sfc /SCANNOW for some reason and then restarted my PC and here I am.
I don't even know why I did it or if I even got the order right cause my head is such a mess right now and I'm desperate to get my PC working again cause I need it for school and I've got nothing else to do in this lockdown.
I don't even care about keeping any of my files, I just want to reset or reinstall Windows so I can use my PC again. If anyone knows anything that could help me then please let me know.

Here's what I've tried to do:
1. Login, obviously doesn't work.
2. Restart doesn't do anything either.
3. Reset my PC with both the keep my files and remove everything option. Eventually goes back to the lock screen or the "choose an option" menu when it's at around 50%.
4. Startup repair. Goes back to the lock screen/choose an option menu.
5. Uninstall updates, same thing.
6. System restore. I don't have a restore point although I'm pretty sure I made one a while ago.
7. System image recovery. Can't do anything there either.
8. The "use a device" option with a USB. Also loads for a bit and then goes to the lock screen.
9. I wanted to boot to the USB from the boot menu but I can't access that or the BIOS.

My specs are as follows:
GPU: GTX 1060 3GB
CPU: i5-2500k
SSD Windows drive: 256GB SSD idk what exactly
HDD Storage drive: 500GB not sure either
MOBO: Some intel one, not sure. Will update soon.
RAM: 8GB DDR3

I'm sorry if the formatting is bad, I'm writing this on my phone.

:)

 

access BIOS settings in Win 10

I have an 8-year old computer running Win 10. I need to access the BIOS settings. It used to be the holding down the F2 key during startup would bring up the BIOS screen in Windows computers. But this no longer works. A web article listed a complicated
series of steps leading to a reboot . . . but still no access to BIOS. Any suggestions?

 

Windows 10 Tweaks

Pressing “Windows+Pause Break” (it’s up there next to scroll lock) opens the “System” Window.

Windows 10: In the new version of Windows, Explorer has a section called Quick Access. This includes your frequent folders and recent files. Explorer defaults to opening this page when you open a new window. If you’d rather open the usual This PC, with links to your drives and library folders, follow these steps:

• Open a new Explorer window.
• Click View in the ribbon.
• Click Options.
• Under General, next to “Open File Explorer to:” choose “This PC.”
• Click OK

credit to Lifehacker.

 

Resolving login issues

If your device doesn't run in safe mode, the next step that we suggest is to run a repair using a boot media. Here are the steps:

• Restart your device.
• Upon start up, keep on pressing F12 to check if your device respond to BIOS.
• Once you've accessed the BIOS setup screen, follow the step-by-step guide on Yashwanth Kotakuri's
  
  post on how to repair start up using a boot media for Windows 10.

Let us know if you need further assistance with the repair.