Depending on your device, you might already have a built-in QR Code reader or scanner.
Open the camera app on your mobile phone and hold it over any code for a few seconds until a notification pops up (you may need to tap the notification). If this doesn’t happen, check your settings and see if QR Code scanning is enabled.
Still not working? Don’t worry, all you have to do now is install third-party QR Code readers from your app stores.