As Tangle mentioned above, you must first reach a certain "post count rank" before you are permitted to access certain areas of the forums. For places like Roleplay World, you merely need to reach a total of 5 active posts in order to reach the rank of "Muffin". For the Debate Pit, you may view all topics within the section at 40 posts, but are unable to actively participate in such threads until reaching a total post count of 100. You can view your current "rank" and posts required for further ranks by clicking on the image below every user's avatar.
So, try and participate in a few other threads of interest to you and soon enough you'll be able to get where you need to. I hope this information helps!
More then likely in this situation the user was a duplicate account of a member who has been previously banned from the site, and has attempted to create an alternative profile, so they go about re-adding all of their previous friends.
Dark Horse's post in I am unable to post in certain forums, and I cannot look at certain topics. was marked as the answer