p.enes.lv is a Fediverse instance that uses the ActivityPub protocol. In other words, users at this host can communicate with people that use software like Mastodon, Pleroma, Friendica, etc. all around the world.
This server runs the snac software and there is no automatic sign-up process.
screenshot #2 seems like maybe it makes sense if it's a reply or a subpost to something
screenshot #3 is like 3 layers of "don't mention his name"