how some people start off being a mod discord of a project

e.g. (he's just an example of many) this guy from elixir active in various projects as a mod

i feel like there might be some 'group' or some specific site/network that shares discord mod jobs

and it tends to be the same group of people repeatedly serving as mods.. ive checked a few people, and it turns out they are the same ones ive seen in other projects; they just change their names

so, can anyone guide me the way to start off this kind of side gig/work

/much thx