As your publication grows, you will want to move from one page to another. To do so, look at the bottom of your screen till you find the following toolbar.

You can navigate back and forth through your publication by clicking the forward and backward arrows.

You can also zoom in on your page, so that it appears bigger.  (It does not actually change size - it just appears bigger on your screen, so that you can more easily position frames and so on).  Using the F9 key will have the same magnifying effect.