When you rollover a Lesson or Section, you'll see a light gray control on the left. You can drag and drop the Section or any Lesson within it to the place that you want to put it.
When you click Edit, you'll be taken to the Edit Section or Lesson view. The 3 dot menu will give you a few more options, including the ability to duplicate that Lesson or Section:
Lastly, when you check the box next to the option to drag and drop the Section or Lessons into a reorder, you'll see the quick option on that Lesson or Section to make Visible or make Hidden, or adjust the Unlock Settings.