Activate FaceTime and Messages on Wi-Fi iPad with email address only?
it is possible. I'll try to walk you through the process in the best and clearest way possible.

Create an iCloud account. (You can create this with an existing email address, just click the “use my current email” button)

Go to “Settings - Messages - Send and receive” than make sure the email you want to use is checked in both the “receive” and “start” sections. (I know we are setting this up in message settings, it will also apply to FaceTime)


Go to “Settings - FaceTime” and check the email in both the “Caller ID” and the “You can be reached at” sections. You may have to scroll down.


You're done! Open the FaceTime app and begin a call! Note that if you only have the wi-fi model, you will need to be in wi-fi.


Hope this helped!