It is advisable that you change your password regularly to prevent your server from getting compromised.
To do this, first you need to be logged in to WHM then from the search bar on the top left of the screen, just type in “root”. (Don’t know how to login to WHM? Click here)
You will then see the “Change Root Password” option on the left pane. Click on that and the Change Root Password screen will show up. You may now proceed in typing your preferred new password.