2 way communication using webrtc?

I'm trying to learn how to use webrtc to allow users to have a 2 way communication via webcam and audio.

I have come across this: LINK

Which i thought was perfect for me to start learning as it seems quite simple and straight to the point unlike other stuff that I found on google.

however, I really cannot make this work on their own demo and on my own server!

I only get my own webcam view in a small window and I cannot find any links to share with someone else!

I thought this: <a id="link" target="_blank">Video Link</a> would be the link to share the chat session with someone else but there is absolutely nothing happening when i click on that link.

the main reason I've chosen to use the code shown in the link above was because it doesn't seem to be using any plugins unlike others.

the question that i have is that am I missing something to make this work?

or Do I need a plugin to make webrtc to work for video/audio P2P chat?

any advise would be appreciated.