Navigating around is easy, just swipe left or right to hide or reveal one of the 4 navigation panes or use the < close or > open toolbar buttons.
If you have a keyboard you can also use the directional arrow keys ↑↓←→ to move between the Library, the Notes List, individual notes and the editor. The panes from left to right are:
The Library - where you can categorise your notes into Groups, Folders and Subfolders and select notes that fit into the predefined Library categories.
The Notes List - where notes are displayed that match your current selection in the Library. The list of Notes can be sorted by last Edited Date, Alphabetically ( ascending or depending based on the nNote's title) or be first Due Date of any of the to-dos within a Note. Notes can also be searched for by using the search bar
The Editor - where you create and edit your notes and tasks. A toolbar appears at the bottom of the editor showing common quick actions and if you have a keyboard there are quick actions linked to shortcut keys. To see a list of these shortcuts in iOS hold down the ‘Command’ key
The Task Editor - a special editor to help you complete the details of your tasks/to-dos