It’s a PC.

Get Proton GE:
This is a quick install that can help with compatibility in various games. See the link for written guide on installing.
It is as easy as entering desktop mode and installing through the Linux App Store.

Get Decky Loader:
It’s a fairly quick install that allows you to browse and install homebrew apps. All are integrated into the “…” button menu.

My main recommendation is to install Decky so that you can install Proton DB. It’s a compatibility database that’s more extensive than Valve’s own Deck compatibility check marks. It adds a rating for all games in your library from broken, bronze, silver, gold and platinum.

It also allows you to install plug-ins for fan control, custom themes, custom boot/sleep animations, a cache clearing utility and so on.

Don’t change your TDP:
From my understanding thus far, it’s much more ideal to lock the frame rate, refresh rate and/or GPU clockspeed and not alter the TDP itself for battery life gains/performance.
Or just leave everything as is, it’s not like you’re leaving the house with this breeze block sized handheld. So you’ll always be close to a charger at home.

Recommended games: Feel free to recommend so I can update this list. These are just my personal picks thus far.

-The Binding of Issac
The GOAT rogue-lite, it runs flawlessly and is very easy on the battery usage.
-Fallout 3
An older game that runs very well and without any stability issues in my time with it.
-Crysis Remastered
Unsurprisingly it runs, and it runs quite well too. I played on medium settings, high textures and at 40hz.
Probably a terrible MOBA, but it scratches an itch for me. I’m running it on low settings, high textures. 80% resolution with AA enabled. That gives me a locked 60FPS in PvP.