First of all you need to purchase cPanel license from cPanel store : https://store.cpanel.net/cart/
Once you purchase license or If you already have active cPanel license, please follow steps below:
– Logon to SSH terminal
– execute this command in shell and wait until it complete: /usr/local/cpanel/cpkeyclt
Here is list of cPanel account tiers and license pricing: https://www.cpanel.net/pricing/
cPanel also offer Partner licenses for:
– WHMCS (billilng software by WHMCS)
– Imunify360 (by CloudLinux)
– WordPress Toolkit Delux for cPanel (by cPanel)
– Sectigo SSL Certificates