You can get and use either the Steam version or the Microsoft Store version. To use the Steam version, vou have to sign up and use the Steam website to use the progra. That means you'll need a network card and an active Internet connection. Go to the Microsoft online store to get the Microsoft version.
Runs under Windows and MacOSX (runs on a PC or a Mac) The version on the Microsoft store can run on the PC, Mobile, Xbox console, Surface Hub, or HoloLens
A 64 bit processor only
1 GB RAM
100 MB for the install directory.
No sound card required