How to determine "Address" to send files to IPAD

I have no problem at all sending files to Kindle.

But I don't seem to be able to determine how to "address" my Ipad 3Pro.

It has a "wi-fi" address (MAC Address) and it does do email...but do I use MY normal email, or do I need some other type account in order to send them to the Calibre application on the Ipad.

I should know how to do this, but I am missing something.

Thanks for any help.

jp