If you’re sure you no longer need a particular notebook, you can delete it from your OneDrive account.
Warning: Deleting a notebook completely removes all of its sections and pages. This happens immediately and cannot be undone. If you’re about to delete a notebook that you have previously shared with other people, consider first notifying them before you inadvertently delete any important notes that others might have only recently added to the shared notebook.
If you’re sure you want to proceed, do the following:
In your browser, go to http://www.onedrive.com, click Sign In, and then sign in with the account on which your notebook is stored.
On OneDrive, browse to the Documents folder, select the notebook you want to delete, and then click Manage > Delete.