I did not quite get your question.
MOCA is pretty straightforward and works (logically) as powerlines.
You need the same adapters (minimum: 2) same model to avoid problems of connection, and various others. Please check the specs as most adapters will top at 500mbps rated (much lower in practice).
The first adapter will take a LAN from your router or any other LAN port around the house connected to the router (or a switch for that matter). It will then have one (or two) coax. One to inject LAN onto coax, the other to passthrough antenna signal to a TV apparatus nearby.
On the other hand, the second adapter will be used where you want to get ethernet. It will have the same one or two coax ports, extracting LAN on the former (LAN output) and passigtrough antenna to the latter.
You can plug in as many adapters as you need around the house, but just as it is with powerline, speed will depend on your coax cabling AND on the connection between adapters (once more, use the same adapters)
WAN port on the back of your router should connect to your ISP (except in more complex scenarios with two or more sub LANs). So leave it there