How does OneNote for iPad work?
When you sign in to OneNote for iPad, your notebooks on OneDrive sync with your device. If you don’t already have a notebook, one with your name is created for you.
If you have OneNote 2010 or OneNote 2013 notebooks on your computer and want to access from your iPad, you’ll need to first put them on OneDrive or SharePoint.
If you have notebooks in more locations, you can sign in and sync those notebooks with your iPad.
To sign in to additional accounts, tap Account > Add a Service and follow the instructions on the screen.