How to progress through Voobly.

Hi there,

I am new to this game and after I bought it on the steam, I decided to try to play it on Voobly. I have been playing for couple of days now in New Player Lobby. I am not sure however how does one progress around different lobbies. I know, that medieval siege lobby is for better players, but I don't know how much elo should I have before I move from Beginner's Lobby. Do you guys have any experience with this, that could help me? :)

Thank you in regard