Go to System Settings > General Settings > Miscellaneous.
Here, you will find the second option that displays the ID Card Scan Code.
Simply enable the QR code/Barcode option by clicking on it, and then click on the Save button.
Now, Go to the Certificate tab and select Generate ID Card, then select criteria and click on search button.
Student List will open below, now check the Checkbox next to the student name whose you want to generate the id card then Click on Generate button.
Student ID card will be generated successfully and on this student ID card you can also see the QRcode/Barcode which is showing in below.