The Skype installation procedure should go through configuring your audio and video. Options to do that should also be on its menus; sorry I don't use Skype often enough to remember exactly where they are, and I'm at work right now so I can't check. I'll mark this thread though, and try to check in later when I get home.
it should be automatic but check your settings. Open the charms menu (while in Skype) click privacy and make sure you are allowing it to use your camera.
In Skype, click on Tools, then Options, then choose Video Settings on the left. If some other program has grabbed the camera (e.g. Yahoo Messenger), you'll need to exit that program.