“How is the wifi antenna connected do you connect it to a cable in the wall that is already existing but I have no cable service?”

This question is for: Cudy - AX3000 Multi Gigabit Dual Band Wi-Fi 6 Mesh Router, 2.5Gbps WAN RJ45, 4 Gigabit RJ45, 4 5dBi Antennas, MU-MIMO, VPN - White