Using To Do and OneNote

If you link the app to Office 365 as described in Linking your task list to Microsoft To Do and OneNote, the app will prompt you to make a linked To Do list when you make a new task list in the app.  It will post your tasks to the linked To Do list, and it will keep the local list and the on-line To Do list synchronized.

The app will also prompt you to link each task list to a OneNote notebook.  Then it will link each task to a section in the notebook, so you can post notes to the linked notebook section from within the app.