The new upcoming Fallout game isn’t going to launch on Steam, and will be available through bethesda.net only. The game’s page only sports a generic “PC GAME” logo. A Bethesda rep stated this in an email:
This is going to make many people unhappy, as this would involve them downloading another launcher just to play one game."The PC version of Fallout 76, for both the B.E.T.A. and the launch, will be available only via Bethesda.net, not on Steam."
Source: https://www.google.com/amp/s/www.pcgamer.com/amp/fallout-76-wont-launch-on-steam/