nginx – WebRTC server’s webcam streaming

I would like to implement a WebRTC based streaming service on a computer with an attached webcam so whenever a user connects using web browser to the IP address of that computer the video stream starts automatically playing.

I use NGINX as the server for the landing page, but I am lost with P2P and S2C concepts. Most of the examples I found would open the Client side camera and not the Server side as I wish.
I am interested in a simple solution without a dedicated media server (Janus..)

My plan is to have maximum 4 users connected at a time, so basically this is P2P and not broadcasting.

To make things a bit more complicated the computer has an integrated webcam which I wont use and instead use the USB attached one.

Any input would be very helpful.