What clients see first

A service on a cPanel server shows an Open cPanel button under Usage once the account is active. It signs you straight into cPanel in a new tab with no password to type, landing on the cPanel home where File Manager, email, databases, backups and the rest are one tap away. The sign-in uses the account's own credentials that WHMCS already holds, so it needs no special server privilege and the app never exposes the password. Landing on a specific tool rather than the home is not offered: after sign-in cPanel only accepts links carrying that session's security token, which is created at login and cannot be known beforehand, so a direct tool link is always bounced to the home. If the button is missing on a service you expect it on, it states why.