You can do all these things using category settings and custom groups.
There are several topics that deal with these configurations, just use internal research
Basically you can create an “Audi Australia” group and you can configure the group so that users can enter only if approved by the owners of the group or only if users register with a particular email domain (e.g. audi.australia@your.site.com).
After that you need to create an “Audi Australia” category and you have to configure the permissions to “create see and reply” only for the “Audi Australia” group.
No one outside the group “Audi Australia” will see that category or see the topics that belong to that category (except for the staff of course).
All the categories with the “everyone can create reply and see” permissions will be public
No, users can’t create groups and categories. However, they can (usually) create PMs, and invite whoever they want to those, but they’re not “in a category” in the usual sense.
You also consider that the creation of automatic groups by users can be deleterious.
You could have dozens of groups dealing with the same theme that have a similar name.
Paradoxically, your users could create:
Audi Australia
Australia Audi
Audi Australia group
Australia Audi group
and so on…
before realizing that there is already an Audi Australia group. Or worse, a user could join the group, find users he does not like and create an Australia Audi group etc…
The simplest thing instead is:
create the Audi Australia group
make the group visible to everyone
configure the group so that users can enter and exit freely
giving “create see reply” permissions only to group Audi Australia in category Audi Australia
관리자가 채팅 채널을 생성할 때는 반드시 특정 카테고리와 연결해야 합니다. 그러면 해당 채널은 연결된 카테고리의 보안 설정을 상속받게 되며, X 그룹이 Y 카테고리에 접근 권한이 있다면 Y 채널에도 접근할 수 있게 됩니다(채널에 설정된 옵션에 따라 자동으로 추가되거나 수동으로 채널에 가입하는 방식이 적용됩니다).