Instance jitsi-meet help

I would like to send you a message because I am trying to find out how to configure certain jitsi-meet instances that would require a no user and other instances where it would not be needed, in order to create private and public instances.

is that possible? And how can we do that?

Would have more concrete examples for example my jitsi is installed on my domain, how to make certain instance via the same domain can use an instance without a password

I try to make sure that some instances are secure with passwords and others are not.
example when I go on the “toto” instance I am asked for a password and if I go on "toto2 la we can connect anonymously.

You can configure use of password following the steps in the link above. The other instance you configure it a no other way

I have looked in detail at the links that you have sent me actually this allows to define an identification to the whole server, I try to make sure to program instances that would ask for passwords and others not, In sum, the name of the instance and its associated password are set directly in the file/etc./prosody/conf Avail/mondomaine.cfg.Lua

This, for me, means different instances of deployment.
If you want some rooms to be locked with a password and some not, if you want this to happen without someone joining and setting a password, you need to write a custom prosody module and implement it yourself.