This is a simple setup. Basically, you just need to install
v4l2loopback for your kernel, sometimes a DKMS module.
Run this to load it manually, if it isn't automatically loaded and configured in your /etc settings:
sudo modprobe v4l2loopback exclusive_caps=1 card_label=<camera label>
For camera label, I went with "camerafun" but any alphanumeric string will work. This will be the name of the video source.