Creating seperate enviroment for each new users

Hi. We are trying to solve a certain issue and would like to hear if anyone else have any idea of how to do this.

We would like new users that sign up to our nextcloud website to be given their own enviroment where they are restricted to certain applications, and can only see/contact users that we have designated (both on the site itself and on apps such as talk).

One solution we were thinking about was creating a new temporary group for each users and granting this group the rights to use the apps we want them to be able to use. However we also need some way to prevent them from being able to contact other users (besides those we designated, which could be specific groups).

Are there any solutions to create something like this? Or would we have to use another type of user management system? Perhaps with a LDAP user system? If anything is unclear ask and I’ll try to explain.

I’ve been investigating this without any results. What we basically want is to decide what groups/users a certain group can talk to. For example we want the “New Users” group to be able to talk to the “Moderator” group, but not to other “New Users”. Are there any solutions to this?