Question - RPG/OpenWorld style multiplayer

[pietru2004]

Hello I wanted to ask is it required to create match to use nakama server.
Is it possible to have it open world style that server has limit of X people and X people can join server and be visible dynamically to each other.
Also is it possible to have servers as shards that share information?

I ask cause I am trying to make game that has global map and allows to join private rooms in certain areas...
example -> vehicle garage...