Can I use Jitsi for my clients, without me as a moderator?

Hi! I would like to know: If I start a meeting at any moment, would this room URL be valid for the future? So I can send to anyone and different people could join this room, without me, in the future.

There is no persistent meeting room in Jitsi. The room is created when the first participant joins and destroyed when the last participant leaves. So rooms are always available.

When you send the meeting link to anyone, the room will be created when they join (if it is not created already)

The first participant becomes the moderator by default but it is possible to change this behavior if this is your own server.