Steam Multiplayer Issue - One session for everyone!

Hi! First of all thank you for clicking and reading, any help will be highly appreciated!
So let me explain the situation. I’ve been working on an online game through steam in UE v4.15, (with the ADVANCED SESSION PLUGIN) managed to get steam connection working.
I’ve seen a lot of tutorials on how to ‘HOST’ sessions and join them - making that is not a problem, although I don’t want that in my game, It’s meant to be more of a MMORPG styled game where you create your character and then join a server.
So what i’m trying to do is have a player open the game>see available server called ‘leaf’> press on it and join the session. I don’t want everyone hosting their own servers where others can join, i want to have a server already pre-created so people can just join it.

Has anyone else had an issue like this or has everyone followed the ‘Host server’ hype?

You can make a dedicated Server with UE4.

Look at this:

Hope this helps.