Inviting someone for a future meeting

Is it possible to program a future on meeting and send today an invitation for this future event ?

Sure thing! Meetings are created on the spot, so all you need to do is come up with a name, and send the URL to the participants.

It is therefore not possible to program them in advance.

A meeting/room is created when the first participant joins and destroyed when the last one leaves. There is nothing to do in advance other than creating a good random name for the meeting and creating the URL to add it to the invitation you will send.