Update Apple TV to new WiFi
How to change WiFi on Apple tv
iPad 2 Wi-Fi
How to change WiFi on Apple tv
iPad 2 Wi-Fi
I am assuming you have your Apple TV already connected by wire. The network setting will not show WiFi, but as soon as you disconnect it, WiFi option will show up and ethernet will disappear. Hope this helps.
Using your remote you would go to settings - network
The OP made no mention of that. They are simply trying to set it up on a new Wifi network. Also, the post was from a month ago so they are probably long gone.
Update Apple TV to new WiFi