As was stated above, I don't think we know for sure, but I can tell you a bit of how it works on the PC. Yes, you can name your room/server as you please. Yes, you can force default setups (or a particular setup, I believe). Once you're in the room/server you can't change anything, so you're stuck with the car/track/settings you started with unless you shut the server down and restart it with new settings. You can choose how many sessions you want (practice, qualifying, race) and how long each session lasts but once it starts it all goes automatically so you can't restart a session or skip a session (there's an app to skip/restart on PC but it's third-party so likely won't be included). You can select the time of day for your session as well as the weather (sunny, cloudy, foggy, rain/wet is not an option) but it stays at that time/weather for each session (meaning you can't have practice in the morning, qualifying at noon, race in the evening).
Things you (unfortunately) can't do:
Reverse grids
Rolling starts
False starts
Choose your livery
Change car/track settings once the session has started
Voice chat (on PC anyway, could be added for console)
It's pretty bare-bones really, but all the basics are there to get a race going.