How does the wireless router connect with a WiFi antenna?

Here at my house, the Wi-Fi antenna is just for the connection from the devices (computer, tablet, roku) to the router. The reason the router works is because it has a cabled connection to the ISP, Spectrum Internet. The router acts at the default gateway for all the devices. So the home itself is like a tiny LAN. I happen to have an Ethernet cord on my laptop, and true to form, it is in the network at 192.168.0.2. (The gateway is 192.168.0.1 - one less.) IP addresses are best assigned via DHCP. If statically assigned it leaves room for a lot of error and it's unnecessary. The only devices that benefit from static IP addresses are printers and servers.