On the bottom right-hand side of the certificate there is a QR code that can be scanned to verify the certificate. This can be done by opening the camera on a smart phone or tablet and holding it over the QR code. It should automatically offer the option to open the online version of the certificate. Alternatively you can use a specialist QR code scanning app. On Android devices you can use the built-in QT scanner or Google lense. On IOS devices you can try this app or this one.