You are not "barely computer literate". Most people have no idea how to put a OS installer on a flash drive and boot from it. If you know how to format your laptop and reinstall Windows, you know how to install Linux. Install any beginner distro (Ubuntu, Linux Mint, etc) and have fun. Google is your friend if you find any issues. There are a lot of resources online to help you.
If you want to play games or use any specific Windows-only software you may have to do some research, but if just for browsing the web you will most probably have a good time. Don't be afraid to try and learn.
This fork is more up to date: https://github.com/Universal-Debloater-Alliance/universal-android-debloater-next-generation
Have you tried updating the controller's firmware?
The game has memory leak issues, causing it to use much more ram than it's supposed to. This is costing them a lot of money with the official servers, so I assume this is top priority for them to solve. Let's hope the upcoming patches fix this very annoying issue!
Having an option to pause the server if no one is online would be nice too to avoid pals starving and getting sick...
The Ryzen 4800U APU is weaker than the Steam Deck, but I'm sure it'll be able to run plenty of old AAA games, indies and emulators
I'd rather have better hand grip and ergonomics than small form factor. I used to play on my PSP and DS/3DS all the time, but yeah nowadays the Steam Deck is the best for my hands
I recommend getting the OLED 512GB because it can store plenty of games and it's better in every way over the LCD model.
If your budget is absolutely limited, then the LCD model is also great.
Clothing, accessories, etc. I remember back then buying hoodies from the Canonical Store, but they are not available anymore.
If there are any, please share web stores where we can buy some FOSS merch and help the community!
Have you tried lowering the resolution and enabling FSR?
Use Luxtorpeda as a compatibility tool and OSRS will run using RuneLite and track time:
Check this video: https://www.youtube.com/watch?v=A7oxT6oSun0 Starts from minute 5:00
You can easily cheat that achievement by changing the clock of your PC, so not a rare achievement, but for the ones that really wait 5 years, that's impressive commitment
A friend once ordered a box of 50 to share with students from university and they delivered to the other side of the world not even charging shipping!