As you are the owner of a VPS or Dedicated server account, WHM gives you the ability to create and manage multiple cPanel accounts. These all may be yours or your clients on your servers have their own cPanels.
Resetting a cPanel password
Here are the steps to change the cPanel password:
1. Login to WHM
2. On the left side Menu panel, under the Account Information section, click on List Accounts. This displays all cPanel accounts under your WHM panel.
3. Find the cPanel account using cPanel username or domain name using the Search option.
4. Expand corresponding cPanel user for which you want to reset the password by clicking on + icon.
5. Enter the new password in the Change Password field and click on Change.
6. That's it. The new password is set for your cPanel account along with the password of default mail and default FTP account