Question How to fix white underscore blinking in the top left corner?

[Balyeeticus]

Just today, I started up my pc, everything was the same and I didnt change anything. But for some reason it started, then showed the white underscore blinking. I tried removing my ssd and plugging it back in, nothing happened. And when the ssd was removed and tried to boot up, same problem, it didnt tell me that it couldnt find bootup which might be strange. Any help?

 

[Balyeeticus]

Sorry, i see an error in what i wrote, when my ssd and hdd arent plugged in i goes straight to bios. Not the white underscore.

 

[Colif]

well, with no drives there, it would go to bios.
Did you try restarting PC after it showed the currsor?

Is this a custom made PC or brand name?
If brand name, what make/model?
If custom, what motherboard?

Its possible the boot method has swapped and all you need to do is swap it back to normal.
Its possible the hdd with the boot partition on it stopped working

Do you have a win 10 installer? could boot from it and see if your drives still show up in cmd
Installer - On another PC, download the Windows 10 media creation tool and use it to make a win 10 installer on USB

Boot from installer
On screen after language choice, pick repair pc, not install
Pick troubleshoot
Pick advanced
Pick Command Prompt
Type diskpart and press enter
Type list disk and press enter
This will show the list of drives currently attached to PC, are they all showing?

screenshot might help. (upload to image sharing website and show link here)