My brother brought me 2 machines like this over the last 2 months. Bad news was they had no recovery media but the good news was both were running W10.

So their files safe on backups I created a Windows 10 install USB stick for other computers using the Windows 10 Media Creation Kit. I booted that and in both cases used the Windows 10 Reset This PC feature to bring both back to full operation.

There's a lot of malware out there and nobody is admitting what they did to blow up either PC but I suspect cracked software or torrent use.