Split article plan and treat each as a prompt

Hi

I want to get in-depth articles about multiples subjects. Quality is not an issue, but the number of words is.

So I was thinking that maybe asking for an article plan, and then asking for content for each part of this plan would be better, but openai keeps talking about other parts of the article and get all mixed up.

This is the prompt to get the plan :
List 4 to 10 subheadings regarding writing a 1500 word blog post answering the question : %question%

And then, in a loop to go through all subheadings :
Write at least 300 words about the paragraph ‘%paragraph%’ that is part of an article called ‘%question%’

How can I be sure that openai will stick to this paragraph subject, and not start talking about other subjects that will be / have been treated already ?

Thanks

Sticking to a certain number of words is difficult.
To follow a certain structure is possible.

Which one is difficult?

Let’s say i would like more than 2 paragraphs while following a structure.