An SSL private key is the secret half of the public/private key pair used by a certificate. It must remain confidential.
In SSL/TLS → Private Keys (KEY), cPanel can generate, upload, view, edit descriptions for, and delete private keys.
Keep secure backups of private keys that must be retained. cPanel documentation warns that a lost private key cannot be recovered. Never publish a private key in website files, source repositories, public messages, or documentation.