There are three ways to capture a barcode to view details for it.

Click the Enter button at the top of the barcodes page, then manually enter the barcode number, you can add the leading zeros or not.

Click the Enter button at the top of the barcodes page, then scan the barcode with your external USB or Wireless barcode scanner.

Click the Scan button at the top of the barcodes page on your mobile phone, then point your phone camera at the barcode. You may need to wait for your phone camera to focus before the barcode is captured.