The visual editor is still under development, so there is no tutorial for it at the moment.
You can try to figure out how to use file the tuesday.js engine, there is documentation for that. to create the basis for your novel, follow this guide:
https://kirilllive.github.io/tuesday-js/tuesday_doc.html#structure
If you have any questions or if you fail, email me at tuesdayjsengine@gmail.com