You can override the shouldRegisterNavigation method on the Page class - to achieve this, you will need to make your own Dashboard class that extends the base Dashboard from the vendor directory.
https://filamentphp.com/docs/3.x/panels/navigation#disabling-resource-or-page-navigation-items
Similarly, you will need to implement a canAccess method to authorize the user to visit the page - since the shouldRegisterNavigation method only determines if it is in the menu.