Add Webcam in a text chat

Hello guys,
i’ve a problem,
i’ve read so much tutorial like kirupa webrtc peertopeer webcam call but anything solve my questions i’ve a text chat multiuser i need to add to everyone a button for enable own cam and when it’s doing appear a button to other user to see this cam
1to1 is simple i’ve read kirupa tutorial for undestanding but for multiuser?
anyone have some notice?
thanks for helping me