The next instalment in the Halo franchise will be up for purchase through Valve's Steam store. Since FPS game would be coming to PC, but details on the storefronts weren't quite as clear.
The PC game to your wish list. Apart from that, it's a pretty straightforward summary of what you'd expect from a Halo game. A campaign mode will see Master Chief battle grunts on a Halo ring, multiplayer returns though we'll need to wait until a later date to see more, and the Forge mode is returning so players can get busy creating new maps and game modes – or in my case, Duck Hunt.
We got our first glimpse at some Halo Infinite open-word game, but 343's Paul Crocker since clarified to us that it's "somewhere between" that and traditional Halo. We also got a peep at Masterchief's toolkit, which involves a grappling hook he can use to pull himself towards enemies or bring items to him.
Quite happily, we also spied a collection of Halo Infinite guns both old and new, which should lead to a decent mix between nostalgia and fresh weapons to try. I may even forgo going invisible and running around with a shotgun, or I won't.

The new PC games in 2020, so there's plenty you can pick there.