Once you have made a new document, go to Window then Pages. The pages palette should appear and you’ll see a list of pages and double-page spreads (two pages you would see next to each other).
At the bottom of the palette, to the left of the trash can you’ll see a little picture that looks like a page. Click once on it to create a new page.
Create a couple of new pages and note that they build up next to each other to create spreads consisting of two pages. It’s a better visual of how your publication will actually look.
Double-click on any page to go to that page. Double-clicking on a page in a spread shows both pages in the spread at the same time. This lets you run images across two pages if you want! Just remember that there may be a gap between the two pages, depending on the tightness of the binding.