With SteamVR you need at least a Gamepad like Xbox, Steamcontroller, logitech etc…
Press & hold select? (Left button of home button) this will open up a big TV mode in steamVR.
You will need seated experience games. Alternately your games can launch directly from pitool.
Some seated games
WarRobotsVR (Free)
Vox Machinae
Detached
Solus Project
Distance
SublevelZero
DCS (free)
Elite Dangerous
WarThunder (free)
House of Rising Sun
Starfighter CDF
InMindVR 1+2