After you inhale that new-iPhone smell, follow this setup guide to be up and running faster than you can say A11 Bionic.
Apple iPhone 8 / 8 Plus - Device Setup - AT&T
Force restart iPhone - Apple Support (PH)
Set up iPhone - Official Apple Support
iPhone 8 and iPhone 8 Plus: A new generation of iPhone - Apple
iPhone 8 & 8 Plus Tips & Tricks You Need To Know - How To Use The iPhone 8
How to lock/unlock screen rotation iPhone 8/8 plus
iPhone Basics: Security and General Settings
Apple iPhone 8 / 8 Plus - Device Setup - AT&T
iPhone 8 Set Up Guide
iPhone 8 and iPhone 8 Plus setup guide: 10 easy first steps
iPhone 8 and iPhone 8 Plus setup guide: 10 easy first steps
How to transfer your SIM and phone number to an iPhone 14
iPhone 15 review: I spent a month with Apple's base model and found it more 'Pro' than ever
Set up your iPhone or iPad - Apple Support
How to Set Up and Activate New iPhone 12, X, iPhone 8/8 Plus/7s