i joined this forum to sell like 15 bitcoins for cash but i can't post or pm anyone since it wont let me
You've created one post, so you should be able to PM now.
Clearly you can post, or I wouldn't have anything to respond to.
Once you have 5 posts and 4 hours of time using the site, you'll be able to post outside the newbie forum. If you had taken a few moments to read some of the stickies as the top of some of the forums, you'd already know this, and you'd be well on your way to your time requirement to get out of the newbie forum.
These requirements help discourage newbies (like yourself) from littering other forums with silly questions (such as this question) that are easily answered by taking a few moments to read the most helpful discussions.