I second this. The initial setup is the hard part. Give it a couple days. The arch wiki is the best resource in the whole Linux ecosystem in my opinion. If that’s the long manual you were looking at for installing steam, know that 90% of it is info on strange edge cases and all a typical user will need to do is sudo pacman -Syu then sudo pacman -S steam (I forgot you have to enable the multilib repository if you haven’t already. You seem smart, you’ll find the info in the wiki)

A couple times a year or so something will break after an update. When that happens

1. Google if anyone else has posted your exact problem
2. See if chatgpt knows anything
3. Humbly post in the arch user forum

One of those will solve it. Good luck!

If you want a wealth of information on what makes a good router/WAP, read https://www.wiisfi.com/. Or skip to the Recommendations section for hardware picks. I do recommend cross referencing for an OpenWRT compatible router