We could see if we can fix it?
On another PC, download the
Windows 10 media creation tool and use it to make a win 10 installer on USB (handy boot drive if nothing else)
boot from installer
on screen after languages, choose repair this pc, not install.
choose troubleshoot
choose advanced
choose start up repair - this will scan PC and maybe fix this - will ask for logon info
if still no good...
I can show you how to save info from here
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
could try a reset
boot from installer
on screen after languages, choose repair this pc, not install.
choose troubleshoot
choose reset this PC
choose keep files/settings (Files = library folders. Library folders = Documents, pictures, movies, music (the default folders that come with windows). Settings = logins and desktop)
If a reset doesn't work
follow this guide:
https://forums.tomshardware.com/faq/how-to-do-a-clean-installation-of-windows-10.3170366/