Prefix's and private categories.

How do I make certain categories Private, so that only certain ranks or groups can see it view it and post on it.

Also can I make it so that if I add someone to a group that they will have their name edited like if I have a clan as a group, and I want to add someone to the group. When they join the group could it add a prefix to their name. Say I'm mamer when I joined the group my forum name is now HG | mamer

ACP > Users & Groups > Group Administration > Then select the group go to permissions and set view to your groups you want to see it...

I have not see any option that can change your username when you join a group.

@Captain Kuchiki wrote:ACP > Users & Groups > Group Administration > Then select the group go to permissions and set view to your groups you want to see it...

I got all the way up to permissions and It wouldnt let me click on view.

Hmmm...ok try this....go to acp > general>forum>forum and categories>
pick a forum that you want to hide, go to permissions and check there view & read and write&reply for the group you want

The automatic prefixes are not available as far as I know, but for private categories you might want to take a look at this topic: http://help.forumotion.com/t38399-restricted-forums