DO NOT use a third-party QR code scanner app.
DO NOT use any browser other than Safari.
３-１. If you are using a device without a home button, open the Control Center by swiping down its top right side. If you are using a device with a home button, do so by swiping up from the bottom edge. Click on the camera icon.
３-２. Scan the QR code and click on the link that appears
３-３. Allow access to the camera