Query Regarding Multiplayer Matchmaking and online Multiplayer System

I am currently trying to make a 1 v 1 game where an user would just initiate search and would be put against anyone.
I have implemented replication in project and have little idea about sessions.

The issue is that I don’t know about how to do it using dedicated server. From some forms I learned that to achieve this I should create session on server side and pass the information of that session to client. I don’t know how to achieve this or weather this is the right approach or not. Kindly guide me regarding this.
If this approach is right. Kindly let me know how should I create session on server and what kind of information should I pass on to client and how should I do that

Thank you for the time