Can i go back to Win 10?

[Smoke420]

long story short my wife's laptop came with win 8.1, I upgraded to win 10 awhile back. Today my wife did a recovery and set it to revert back to the version of windows the laptop came with. my question is can i get back to win 10 from 8.1 after reverting back to 8.1? Ty in advance

 

[Smoke420]

awesome ty! would i do it through windows update?