Access webmail from the cPanel interface

To access Webmail from the cPanel interface, either click the Webmail icon in the Mail section of the cPanel Home interface, or perform the following steps:

1. Navigate to cPanel’s Email Accounts interface (Home >> Mail >> Email Accounts).
2. Click More in the row that corresponds to the email account for which you wish to access Webmail.
3. Select Access Webmail.
4. Enter the password for the selected email account, and click Log In.
5. Select your preferred webmail application (see below).

How to select your preferred webmail application

To select your preferred webmail application, perform the following steps:

Click the logo or the Read Mail Using link for your preferred webmail application.The interface for your chosen webmail application will appear.

1. If you are not sure which webmail application you should use, read our Which Webmail Application Should I Choose? documentation.
2. Click Enable AutoLoad if you want the chosen webmail application to load automatically the next time that you access Webmail.

The webmail client will retrieve and display all of your email account’s read and unread messages.

Ref : https://documentation.cpanel.net/pages/viewpage.action?pageId=2719926#HowtoAccesscPanel&WHMServices-cpaneladvanced