Use the buttons and screen on your Apple Watch - Apple Support (CA)

Learn how to interact with your Apple Watch using the Digital Crown, side button, and gestures. 

Set up cellular on Apple Watch - Apple Support (CA)

Use and customize the Action button on iPhone 15 Pro and iPhone 15

Take a screenshot - Apple Support

Organize apps on Apple Watch - Apple Support

Run with your Apple Watch - Apple Support (CA)

Get apps on Apple Watch - Apple Support (CA)

How to Use the New App Store on Your Apple Watch

Unlock your iPhone with Apple Watch when you're wearing a face

Before you buy, sell, give away, or trade in - Apple Support (CA)

Apple Watch - Official Apple Support

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

Apple introduces the advanced new Apple Watch Series 9 - Apple (CA)

Confirm With Side Button — Benjamin Mayo

iPhone User Guide - VCFA

10 awesome things you can do with the iPhone 15 Pro Action button

My Phone's Power Button Had One Job, and Now it's Losing it

iPhone 15 Pro: iPhone 15 Pro to ditch clicky power switch, Apple plans to introduce solid-state buttons on device - The Economic Times