On another PC, download the
Windows 10 media creation tool and use it to make a win 10 installer on USB
USB works, just not in windows.
need to set bios up to boot from USB, what PC do you have? I can help unless you know that already
we can try a few things from windows repair
System restore
boot from installer
on screen after languages, choose repair this pc, not install.
choose troubleshoot
choose advanced
Choose system restore
will need to logon
Hopefully you have a system restore point you can roll back to before your accident
Next choice you have is a reset.
Is there anything on C you want to save? resets sometimes fail so better to be safe -
this shows how to copy info off now before you start
boot from installer
on screen after languages, choose repair this pc, not install.
choose troubleshoot
choose advanced
choose command prompt
type
notepad and press enter
in notepad, select file>open
Use file explorer to copy any files you need to save to USB or hdd
Reset
boot from installer
on screen after languages, choose repair this pc, not install.
choose troubleshoot
choose reset this PC
two choices, remove everything or keep files/settings
choose keep files/settings (Files = library folders. Library folders = Documents, pictures, movies, music (the default folders that come with windows). Settings = logins and desktop)
this removes all the programs on C drive, if you have more than 1 hdd in PC, it won't touch the other ones.
If it still doesn't work after a reset (it should though), you might need to do a clean install. If you copied everything off C before you did reset, its not a very big step - follow this guide:
https://forums.tomshardware.com/faq/how-to-do-a-clean-installation-of-windows-10.3170366/