Dynamically add a content reference to a list of content

I would like to have in a content called "Instance" a field corresponding to a list of another content (called "meeting"). I do not think it's very difficult.
Additionally, in my meeting content I have an "instance" field that refers to one and only one instance. So I would like to see that when you create a new Meeting, the meeting is automatically added to the list of Instance content created earlier.

Is this second part realisable ?

Regards,
Nemtecl - French student