my_hat_stinks

It’s an analogy, the specific case doesn’t matter. It demonstrates that infinite does not mean literally everything, it’s possible for some item to be missing from any particular infinite set. In a box of infinite apples you won’t have an orange; in a box of infinite fruit you won’t have a chicken; in an infinite multiverse you by definition won’t have a universe which isn’t part of that multiverse.

Joining a community centered solely around content you want to avoid seems counter-productive.

A server is just some computer somewhere that other machines can connect to. You can get specialised hardware and network setups and other technical stuff, but you can also just use your personal laptop as a server by allowing people to connect to it. A server essentially boils down to someone leaving their computer on.

Wifi is just radio waves. You can think of it like people talking on a two-way radio, except instead of humans speaking it’s computers.