Open the Camera app
Point the camera at the QR code
Hold the iPhone steady
Wait for the QR code notification to appear
Tap the notification to open the link or action
If it does not scan, make sure QR code scanning is enabled in Settings
Open Settings
Tap Camera
Turn on Scan QR Codes
If needed, use the Control Center QR Code Scanner
Swipe down from the top-right corner
Tap the Code Scanner icon
Point it at the QR code
Tap the prompt that appears