i want to create a room based multiplayer game where a player hits the Play button,and is automatically matchmaked with other player with near or equal levels and transition them to a lobby similar to League of legends.
What are you asking exactly?
^ Networking Basics
^ Multiplayer HUD tutorial
^ Should help with the basic match making/ networking side of things.
Mate, this took me a grand 15 seconds to google search and paste the results, look before you ask questions. Also keep in mind that based on your lack of googling skills this task of creating a multiplayer game (which is very complicated) may be beyond your level of skill for the time being.
Remember to familiarize yourself with whatever engine you are using, and learn its ins and outs before attempting to create a project, specially one as big as this one.
my question was how to create rooms(i mean sessions) that players can only join…not lobby or OSS which i know of course
I don’t think this is possible with just Blueprints.
The only Session actions you can perform are
Starting basic ServerSessions
Searching them in LAN or Online (Online only with a valid Subsystem like Steam)
and Join them after you found one
For Matchmaked information like PlayerLevel etc, you will need C++ i guess.
Because without joining a session, you can’t get information from it in BP.
But in C++ you could extend the Session Class and SearchResult Class and
add Information to them that would help determining the correct session.