From GameWatcher: “Fallout 76 is out now, but one of the more annoying aspects about the game is that it’s not available on Steam. While this isn’t game-breaking, it does stop you using all the neat features of Steam. So, we’ll show you how to use the Fallout 76 Steam Overlay.”
Source: N4G PC Fallout 76 Steam Overlay – How to Use Fallout 76 with Steam