Send live stream (local network url) in video call

Does WebRTC support call from device media (camera, microphone) only or we can send a stream from another device as well?

For my case, I have a device that streams video on a local URL, I want to send this stream (local URL stream) instead of the stream (from my phone’s camera) to another user who is on call?

Is this possible to achieve this using WebRTC?