If you're having trouble getting Milo's green light to turn on, there are several things you can try in order to find the best possible connection for your Milo.
First, consider whether there is any other way you could arrange your Milos. The best arrangement will depend entirely on your unique home layout, but in general, Milo works best when each Milo is placed out in the open, such as on a side table or counter; and we recommend aiming for up to 40 feet between Milos. Depending on your specific needs, this might mean you need to create a "bridge," by placing one Milo in between the base and another Milo, so the connection can reach the furthest Milo.
If your base won't connect to your modem, we recommend checking that DHCP is enabled over Ethernet ports on your modem.
We also offer some more tips about Milo placement here.