So there are two sides of the story here in my eyes, one is where I started. know nothing, set up your stream system and go for it.. have fun and learn/build as you go.
or two is try and aim for the "perfectionist" streamer vibe where everything is very slick, paid overlay,transitions sounds alerts etc. I started when mixer was around streaming from my xbox. now I stream from the pc and both companion app for xbox. I still learn a lot every day I think this is part of the experience and your viewers get to see you grow as a content creator. I don't believe there really is a "do this first" kind of setup. Just have fun and you will succeed
Yes are doing to need a decent pc to run OBS or Xspilt. Along with funds to get microphone and other equipment like Elgato Game Capture. I don't recommended using console streaming option because it has limitations. One more piece of advice is NETWORKING that's the key to become a successful streamer. Remember there is billions of streamers out there but it's room for everyone to succeed in streaming. Good luck