You will find in this article some tips for choosing strong passwords and thus protect your accounts: How to choose a strong password?
To change the password, go to cPanel > PREFERENCES > Password & Security
Enter the current password of the cPanel account, the new password, confirm it then click on the button Change your password now!
You have, on the page that appears, a password generator and tips and suggestions that will help you choose a good password.
From Heberjahiz Customer Area
If you have lost the current password, you can reset it in the customer area of your account from www.heberjahiz.com/client > cPanel. Click on "click here to reset it"
A window to confirm your request will appear, you must click on "Confirm".
An email containing a new password will be sent to the account administrator's address.