Question about Xiaomi AX3000

Yes, of course, you have to do this even with the first mesh router. Use the WAN Ethernet connection for this. The router of the Internet service provider is connected to the Xiaomi Mesh Router with a LAN cable. Then switch off the WLAN at the Internet service provider router and set up the WLAN at the Xiaomi Mesh Router. The mesh will then take over the WiFi operation and the devices connected to the mesh router 3 port switch will also receive their IP addresses from the Xiaomi mesh router.