Defending a single rook ending with three pawns to your two can be tricky, but using your knowledge of the theoretical rook endings already covered should help immensely! The key idea here is that Black is highly incentivized to continue trading pawns. Push your h-pawn up to h5 to ensure White needs to trade down further to make a passer. Good luck!
L.Van Wely-B.Gelfand, Melody Amber (blindfold) 19991...