There are 2 ways to access a menu item in WordPress; this help page will show you both.
WordPress menus run down the left side of the screen.
The menus in WordPress are both expandable or can be accessed when you click on the main menu item. Once you click on the menu item, the menu will expand and show you the sub-menu options.
Menus will also display when you mouse over the main menu. A fly out menu will appear and the sub-menu options will be available for selection.