What do I do to add my program to homebrew?

I’m not entirely clear on what guide to follow to add my program to homebrew, is it this https://docs.brew.sh/How-To-Open-a-Homebrew-Pull-Request ?

The program is a site generator/manager similar to Hugo.

https://docs.brew.sh/Acceptable-Formulae#niche-or-self-submitted-stuff might apply here. But otherwise yeah, you just create a pull request.