You can buy most parts including the battery from ifixit. They have a partnership with Valve for parts. Also they have instructions on how to fix the part.

https://www.ifixit.com/Parts/Steam_Deck

I personally liked the Damnation game. Bought it when it came out on PS3 and own it on steam.

If the other handhelds didn’t run windows they would be so much better.

Steam deck compatibility helps people with low spec PCs the ability to play new games.