The easiest way to do this, to get the formatting you require, is to use multiple ordered lists, one for each section, and then set each list to start where the other ends, using the start attribute on <ol> tags.
I have made an example video creating a similar layout to what you require, starting with all the content formatted as headings and paragraphs.
Each paragraphs is then converted into a new ordered list, and the start values of each ordered list are adjusted using the Ordered List dialog.
For nested lists, you create a new list item using Enter, then indent the list.
Just because you're not paranoid doesn't mean everybody isn't out to get you.