Almost every interface has a security measure to ensure safety measures. Similarly, the Two-factor Authentication is a measure for security that needs two types of identification checks. Once you are asked to enter the password, you will need to out in a security code. This security code is sent to your smartphone and only then will you be able to log in to the system.
However, the smartphone used in this case should support a time-based one-time password (TOTP) application. To make use of this feature, it should be enabled to you by your hosting provider. Follow the given steps in WHM.
Make a note that Two-Factor Authentication allows only one simultaneous session for any user. In case you try to open cPanel from a number of web browser windows and log out of one of them, the user will be directed out from all other windows by the server.
In order to configure the Two-Factor Authentication, follow the given steps accordingly.
In case of a warning message stating failure of the procedure, the probable reason is an invalid security code. There may be a problem with the date and time settings of your system as well. Contact your hosting provider to troubleshoot this issue.
To remove Two-factor Authentication, select on Remove Two-Factor Authentication.
Click on Reconfigure to reconfigure Two-Factor Authentication.
This document states what a Two-Factor Authentication is and how to configure it efficiently.