You can use FaceTime for Android and Windows devices by clicking a link sent to you.
How to Add Android, Linux & Windows Users to FaceTime Calls in iOS 15 « iOS & iPhone :: Gadget Hacks
How to FaceTime between iPhone and Windows or Android devices
How to FaceTime on Android or Windows
How to Use FaceTime on Android or Windows - javatpoint
FaceTime finally on the way to Android and Windows, but there's a catch
How to FaceTime Android and PC Users in iOS 15 - Tech Advisor
How to FaceTime on Android or Windows - Android Authority
Use FaceTime with your iPhone or iPad - Apple Support (CA)
FaceeTime your friends with Android Phones and Windows PCs! #tailormad, android
FaceTime is coming to Android and Windows: Here's what we know
FaceTime The iPhone FAQ