There are many internet community apps out there, and I’ve found a great one called Amino. Amino is basically what would happen if you combined Facebook and Tumblr into one big app. There are different ones, for all different kinds of interests.
How do you get on it? It’s a mobile app. You can download specific communities on the app store of your choice, or you can just do what I do and get the app, and then you have a whole bunch of the aminos in a menu. I’m currently on the Autistic and Aspie, Catholic, DC, Doctor Who, Equestria, Nostalgia Critic, Rock, and Wrestling Aminos. You can either use your real name or make up a username. (I’m Rock Lobster.)