I’ve been reading jitsi documentation for a on-premise installation.
But I’m confused about P2P feature.
I understand that p2p is activated automatically depending on the number of users.
If there are two users on meeting, communications is via p2p? else use JVB?
Or Is there a way to make user-to-user calls?
Yes, an attempt will first be made to establish a two-party call as P2P if possible. Once there are three parties in a call, the bridge is automatically recruited to route media.
By calls do you mean, calling like normal phone calling and answering?
Between two users with Jitsi App
There is no calling feature. It is a rendezvous service, you arrange meetings in advance through other channels - calendar events and such.
If you want, that is possible to be implemented in your custom apps. You can have a calling service in the custom app through your channel of communications and when one answers - put both parties in the same room, this is what people do to implement video calling through jitsi-meet.