Quick Question: Can I download my Xbox games locally to the ROG Ally for offline play?

I’m was waiting to see if Xbox would announce a handheld console today and was disappointed. Now I have the wonderful opportunity to research and purchase a console for travelling.

So can I download games like Elden Ring or Witcher 3 locally to the handheld console? What about gamepass games? I can’t find a conclusive answer online.

Thanks for the help!