On another PC, download the
Windows 10 media creation tool and use it to make a win 10 installer on USB - handy boot disk
i can get you to safe mode
boot from installer
on screen after languages, choose repair this pc, not install.
choose troubleshoot
choose advanced
choose command prompt
Enter these
BOLD commands and press ENTER after each.
(Note the colon after C with no space; then the spaces which are important - one after T before / & T before { & } before B & Y before L)
C:
BCDEDIT /SET {DEFAULT} BOOTMENUPOLICY LEGACY
EXIT
You are back in blue menu, go to top lvl agin -> Shutdown the computer.
Boot back up and "immediately" start tapping F8 (That means power button - then F8).
Hopefully that should get you into Safe Mode.
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To reverse that you can use the same steps and type these (again note spaces)
C:
BCDEDIT /SET {DEFAULT} BOOTMENUPOLICY STANDARD
Restart but F8 will not work now.
i would suggest backing up anything on c you want to save, just in case.