Answer:
Click on the New Slide icon.
Step-by-step explanation:
You need to create a new slide to add more information to your presentation, you cannot just squeeze all bits of remaining info onto previous slides. First, the information might not be related, second it will overload the slides, not good for presentations.
The "New Slide" option wouldn't be in the "Format" menu, since that menu is for the formatting of the text and slides, not to add a new one.