If you need to give your notes to someone who doesn't have access to the notebook file, you can do so by exporting a page, section, or an entire notebook.
You can export a page, section, or the entire notebook. A page and section work the same way. Notice the export file type for a page is the same as a section.
Now there are only three format options. The first packages it so it can be re-opened in OneNote and the second two allow the notebook to be opened in a viewer without OneNote.