At home
If your Apple TV is connected to your network at home and it doesn't get past the date and time screen, try restarting your Internet modem and router.
If you still can't set the date and time on your Apple TV, contact your Internet service provider or router manufacturer to make sure that NTP port 123 isn't being blocked.
You might also try connecting your Apple TV to another network if it's available, like at a friend's house.
At work or school
If your Apple TV is connected to an enterprise or campus network, make sure your network, router, firewall, or proxy server are configured to allow communication over NTP port 123.
You can also use Configurator to create a first time configuration for your Apple TV devices. Connect the Apple TV to your Configurator server using USB, then set up the device using a profile.