The page that you created will now have appeared in the Pages area of your portfolio. In this screen you will notice a couple of icons on the right-hand side, which allow you to either jump back into editing mode or to delete your page.
Now that you know how to go back and change things, try to:
You can use the block descriptions in the next section to make a choice about which new block you would like to add. Try adding one that you haven't used before to see what you can achieve.