Receivin FaceTime calls on the ipad
FaceTime calls come to the iPhone and not the iPad.
Are you able to make and receive Facetime calls on your iPad at all?
Typically, whichever device is active is the one you'll get them on. If the iPad is open (screen not locked) meaning it is actively in use, a Facetime call would come to that device. If the screen is locked, but your iPhone is open, the call would come to your iPhone.
That said, not knowing how you have things configured, see this link --> Make and receive FaceTime calls on iPad - Apple Support