How to separate access rights to sections in Confuence for different user groups?

Question

Wiki engines

Introductory
1. We use Confluence, which has a number of spaces
2. Some of the spaces are public (open to everyone), some are private (available only to employees), some are semi-private (available to contractors and employees)

Task
1. How to organize viewing the public section of Confluence without authorization?
2. How to restrict access to users of one space to another? Namely, how to make it so that contractors cannot view the space intended for employees
3. How to create a user group and divide the rights into spaces?

As we understood, the second point is solved by creating a user group and adding the group to the corresponding space. It is not clear how it works and whether a new group is charged separately and whether the limits for this group are taken into account

Answer 1

1. I don’t know how other companies do it, we only have an application and at the same time they are given the usual role to view all spaces, if they are open of course.
2. You can restrict access to a group. That is, groups are created and prescribed for space. For example, if the space code is RDDT, then the groups will be of the type RDDT, RDDT-admin, RDDT-edit, RDDR-view-ext, and so on. Each group is assigned roles. After that, this space is made closed from everyone who needs access, they simply include it in the group. There are a number of disadvantages here, ordinary users, even space administrators, may not have roles to add users to such groups. Even if there are a lot of spaces, you will have to do such manipulations for everyone.
3. From the above, Jira \ Confluence application administrators create such groups.
There are no limits...