Of course! Alright, to ensure that somebody gets the message you intend for them click the reply button below their message and then type what it is you have to say. Private messaging is quite simple, you just hit the "send message" button when you get to their page. Uh, to write you go to the create button and go from there. And if you're reading something that you like, vote and add it to your reading list (if that's what you want to do with it)
That's basically it. Everyone's super friendly (or, a majority of them anyway), and there are a lot of super talented authors on here.
So welcome to the land of hopeful young and old writers, readers and procrastinators. Enjoy your stay. And please, don't feed the words, they bite ;)