Hello Erin,
Welcome to Microsoft Community.
In order to save/send your PowerPoint slides to OneNote you have to use the option Send to OneNote in PowerPoint 2013. To do this let us follow these steps:
First check if you have Send to OneNote printer driver (generic printer driver) installed. From Control Panel navigate to > Devices and Printers or Printers followed by Devices and Printers. Check if you see Send to OneNote or Send to OneNote 2013 printer driver in the list of Printers. If found then try changing the printer default to Send to OneNote 2013. Close the Printers window once done.
Now follow this step from PowerPoint 2013.
- Click on File > Printers.
- Click on the drop-down below Printer.
- Select Send to OneNote 2013.
- Click on Print.
- Open OneNote 2013 and save it to the desired Notebook or page.
Hope the above information helps.
Thank you.