Got a new I-Phone; can't connect to Apple Watch

Can you be a little more specific? What model iPhone? What model watch? Did you unpair the watch from the old iPhone first? Did you restore from a backup? Without any more info, perhaps this article will help:

How to pair your Apple Watch with a new iPhone - Apple Support

If your Apple Watch isn't connected or paired with your iPhone - Apple Support

Unpair and erase your Apple Watch - Apple Support

iPhone X Apple 3 watch no I did not unpair but I did restore from a backup

Hello?

As javaliga says you need to remove the watch from your old phone before you can do anything else.