Help, adult son thought wood floor was a good place for cat's litter box.

How do you get cat pee smell out, plus mold? My son didn't ever lift it up, so though he cleaned the box he didn't realize kitty missed often. Older cat, so I'm not blaming her either. After the initial clean, I know the floor is going to need sand and refinishing, just need initial help on what to do!!! (I don't live here, please don't judge me.)