Navigation Block appears on every page of the site & includes My Home, Site Pages, My Profile, and Courses. What appears in the navigation block depends on the role of the user, where they are in the Moodle site, and any settings that have been applied globally.
Now you can add custom menu items in the Navigation Block by using the Custom Navigation Plugin. The custom navigation plugin allows you to add new menu items at the end of Navigation Menu in order to customize your options menu. You just have to use the same syntax that is used for the navigation bar on theme general settings.
The Custom Navigation plugin is maintained by Carlos Escobedo and is available for all Moodle versions from Moodle 2.6 onwards. You can download the latest version of the Custom Navigation plugin from the Moodle plugins database from – https://moodle.org/plugins/view/local_navigation
Have you ever used the custom navigation plugin in any Moodle project? What are your views about it? Do share with us in comments.