Flexitarian bicycle commuter (he/him) from the Netherlands.
My Pixelfed account on Pixey.
It is a DE, like regular KDE, GNOME etc. At your OS’s login shell, you should be able to select it once installed. If it is the only desktop environment on that system, it will not even be needed to get selected as the appropriate session gets started when you login.
Arch (and derivative) systems can install it through the AUR, but I do not know any distribution that offers it through their normal distribution channels (packages sources) already.
Old John Brown
This guy? https://en.wikipedia.org/wiki/John_Brown_(abolitionist)
For those that do not get this one: it’s a reference to a somewhat older meme from the late 2010s
FYI, Aegis works on GrapheneOS if you need a recommendation (in terms of an app for 2FA).