The easiest way is to install MotioneEye OS on each pi. It's dead simple and makes it easy to manage each camera. Then you go to the IP address of the camera to manage it (you can easily set a dedicated IP). You can get the stream by using the port :8081.
https://raspberry-valley.azurewebsites.net/MotionEye-OS/#motioneye-os-image
The cameras you buy separately. I have 2 of these. However, the ribbon cable that comes with this camera will not fit the pi zero. The Zero has a smaller ribbon cable connector. These ribbon cables will work.