The location of the menus can vary from theme to theme. All WordPress themes contain at least one menu location. Some WordPress themes contain different menu locations, which suits best for more complex boggling sites.
In order to add Posts, select Posts from the drop down and click Add to Menu button as shown below.
Users can add some links using custom menu section. To add a link, click Custom Links drop down box, enter the preferred site URL and proceed by clicking Add to Menu button as shown in the image below:
Similarly Categories and Tags can be added to the created menu.
The image below demonstrates rearranging the menu items by drag and drop method taking a sample page item is dragged and dropped onto the Home page.
Drop – Down menus are also known as Nested Menus. To create a nested menu, select a main item at the top and that would be the Parent item. Then slightly drag the rest items to the right side of the screen. Now, WordPress automatically creates child menu items for the given parent menu as show in the image below.
From the above image, the URL and Navigation Label can be edited or the menu item can be removed by using the Remove option.