How do I modify the automatic startup pages that I setup originally?

I need to eliminate one of the automatic startup pages and add two more… how do I do this?

Thanks!

@coconut,
To do this:

  1. Go to Main Menu --> Settings
  2. Under the Get started section (should be the first one you see) you should see On startup
  3. Select the Open a specific set of pages option and you should be able to add/remove startup pages as you please: