Organize a Rocket League tournament?

Anyone who has ever watched Rocket League eSport knows roughly how it works, you get a code and then you can enter a room. The organizers can then watch, etc. We would like to do something among friends that there's a host and then some who play against each other. We would do this for 1 day, watch the HOST-PC stream on Twitch and the 28 who are not playing at the moment. How can you do such an eSport tournament?

Look here:

https://www.game.tv/de/find-tournaments/rocket-league-tournaments