[DamianWayne]

but i want it to be accessible , help please

[Bish0pQ]

There is not much explaining you did, and I'm not that experienced with myBB. It might be an option to create a special usergroup and make it only visible to that usergroup? Than it will be accessible only if a member belongs to that usergroup.

[Mr.Kurd]

I always do a change at style, maybe you can find it there..

[DamianWayne]

i meant tabs like sinister

[Skryptec]

You can do this by changing the permissions.
Go to your Admin Control Panel -> Forums & Posts -> Forum Management.
Select the forum/category you would like to modify, then just change the permissions by dragging them.