If you are using the LexActivator, then you must have called ActivateLicense() function to activate the product. It requires that should have called SetLicenseKey() function earlier. So, to generate license keys you click the Product in the products table and on right top click the “Licenses” button, or simply click the “Total Licenses” link in the Products table.
When your customer pays for the product using any payment processor, you generate the license key on confirmation of the payment, and mail your customer the license key and optionally the download url (in case you want to secure the distrubution as well).
When your customer starts your app you check for the license, if not present your customer enters the license key to activate the product and then is authorised to use it.
For web integration part check the following:
In case you want your customers to self manage the license keys, you can create users in the dashboard and link those users with the license key. Then your customers can login to Cryptlex dashboard to see their license keys.