The video below shows the process of How to create dropdown menus (click the button on the bottom right of the video to expand the view). You can also follow the screen shots and steps below this.
6) A new window will pop up. Here you can select the area of your website you would like to link to. For example, if you wanted to link to a page on your website you would select Page.
7) Select the page folder you page can be found in, then select the page you would like your menu item to link to. If you have not created any page folders, you will find all your pages under "Admin".