To change your cPanel password, follow these steps:
Log in to cPanel.
In the PREFERENCES section of the cPanel home screen, click Password & Security.
In the Old Password text box, type your current password.
In the New Password text box, type the new password that you want.
In the New Password (Again) text box, retype the new password.
You can click Password Generator and cPanel generates a random, strong password for you.
Click Change your password now! The new password takes effect immediately.