Steam VR is the system used to support VR gear - if - you have bought the game on Steam. Basically you start Steam, then Steam VR and then fire up the game you want and play it. It’s a product of it’s own so you have to update it now and then just like Steam or MSFS2020.
Some settings are available in Steam VR, but some games have overrides and their own settings. There is usually a VR option in the game to configure this, Aerofly FS2 and DCSWorld have specific VR settings in options menu and i expect MSFS2020 also have that too when VR arrives.