Well, it depends on what the requirements are, but generally you will need a plugin or integrate some C++ code to that project. Matchmaking is usually something that is done “outside” of the game and requires a clever setup of server and hosting. Various games does these things differently, but usually the players end up in a lobby based on their Elo. This lobby is often tricked to communicate with the client without actually hosting anything until all other clients are connected.
I highly recommend learning more about matchmaking before deciding to create such a system. This could perhaps be something to look closer at, however it is very expensive.