Using the CLI Console
Go to Dashboard > Console to access the CLI without exiting from the GUI.
Alternatively, if you want to open the CLI console in a pop-up dialog that you can resize, reposition, and keep open while you go to other areas of the GUI, click the CLI Console button that is in the bar at the top right corner of the GUI, next to the Help button.
For information about commands, see the FortiMail CLI Reference.