I have only one number for supporting FaceTime calls. This is enough considering that most people I know does not have an Apple device to make a call. FaceTime requires an Apple device in order to use FaceTime. With that said, I will assume that I will answer any such calls on my iPhone Pro Max. I will not do video calls. With that said, if you wish to use FaceTime to make a call to me, you would want to make an audio call only.
FaceTime is free to anyone that has an Apple device, and you just need my iPhone’s telephone number which is noted at the top of this page. I have never used FaceTime, so I can’t tell you the procedure on how to use it. If you have any questions on using FaceTime, consult Apple.