You can use a QR scanner to scan the 2D QR code found on the bottom or side of the CPU. If you do not have a scanner, you can use a third party app called NeoReader on your phone. The website suggests to use a macro lens. However, if you not have that and the app's camera option cannot detect the QR code, you can use your phone’s camera to take a better photo by zooming in. There is an option in the app to select from the photo album of your phone: https://www.intel.com/content/www/us/en/support/articles/000021613/processors/intel-core-processors.html