For Insiders through the Xbox App for Windows.
Today, we’re excited to announce we’re bringing Xbox Cloud Gaming (Beta) to the Xbox App on Windows 10 PCs for Xbox Game Pass Ultimate members in 22 countries who are part of the Insider program. Xbox Cloud Gaming with the Xbox App provides the same great Xbox experience you’re used to: Play over 100 high-quality Xbox console games with your friends; pick up from a saved game you started on your Xbox; or try out a whole new game from the Xbox Game Pass library to decide if you want to download it to your console.
With Xbox Cloud Gaming, you can turn all types of PCs into a gaming device, from brand-new budget computers to older machines with low specs. All you need to do is connect a compatible controller via Bluetooth or USB, launch the Xbox app, click the “cloud games” button, select your game and start playing. We’ve also added some new features to help you get started, including easy-to-access information on controller and network status, social features to stay connected with friends, and the ability to invite people – even those also playing on cloud without the game installed – to join you in a game.
Source: Xbox