If a discounted subscription is provided as an employee benefit, there is no product key for the end user (employee).
One logs in to Norton.com with the uid & pw that were set up when the employee started the benefit-subscription.
If installing 360 on a pc, it is done directly via the download function on Norton.com.
If installing on a phone, the website download function will generate and send an email download link. Access that link on the phone and it will install directly from Norton.com same as a pc.
Who ever is responsible for the purchase will have the key in a Norton Account that they manage. Check with that individual to see if they can tell you how to get the product installed.