To use your Office 365 account and sync SharePoint notebooks, add the SharePoint location to your phone.
Open OneNote and tap Open notebook.
If you have a notebook open, on the action bar, tap to go to the Notebooks view first.
Under Other Notebooks, tap Add an Office 365 account for work/school notebooks.
Enter your organization’s account information.
After you sign in, your work or school notebooks will show under Other Notebooks.