Is it possible to change the default for a single page, without affecting other pages?

In this case, I'm trying to change the behavior for a Wiki page on a corporate internal Wiki. I control the page in question, so there is no need for consensus. But, I do not understand what needs to be changed to implement section numbers within the body of the document.

Here's what I read in https://www.mediawiki.org/wiki/Manual:Table_of_contents#Customizing_the_TOC: