Anyone. You don’t need tech skills, and you don’t need much money either.
If you use a managed hosting service, the price starts from around 8 euros or 8 dollars a month and the service will handle all the technical stuff.
Once your server is set up, you can follow people on other servers and they can follow you. You don’t have to do this though, it’s much easier to just join someone else’s server, but it’s there as an option. Many people enjoy growing their own server.
You can find out more info on running your own Fediverse server over on my other site GrowYourOwn.Services ⧉ and there’s a long-form Mastodon server tutorial ⧉ there too.