Adding my vote for Beatsaber. Really is a lot of fun. Or, altternatively, if you don’t like the fairly limited choice of music in Beatsaber, there’s Audio Shield. Perhaps not quite as good a game, but lets you use your own music!
Other good ones that I’ve played… Arizona Sunshine (great zombie shooter), Island 359 (come on, it’s got dinosaurs, what’s not to like?), Vanishing Realms, Skyrim and if you just want to chill, The Blu is really relaxing. Oh yeah… and Elite Dangerous
Small piece of advice. VR can really bring on motion sickness, even if you don’t usually suffer from it. Have something ginger based to hand. Ginger beer, ginger chew, even raw ginger. Basically, anything with ginger in it really helps.