To see the amount of each resource your cPaneluses (like disk usage or bandwidth), look in the Statistics section of the cPanel home page.

From your client area go to:

Services -> My Services -> click on the green "Active" button -> Login to cPanel/Control Panel

In the account Dashboard, click cPanel Admin.

In the cPanel Home page, your account's current resource usage is shown in the Statistics section.

(Optional):

To see if you've hit the limit for your account's CPU or entry processes/concurrent connections, click Metrics and then select CPU and Concurrent Connection Usage.