How to duplicate and modify a "posts" page.

Cheers! I’ve been searching and having issues finding a solution since the keywords are really ubiquitis, but here’s what I’ve got:

This is the “posts” page to a site Im working on:
https://inspirehealthmag.com/inspire-health-ap/

…the content here is specifically designed to populate an iFrame on another website. It contains multiple categories, but I’ve omitted a few as well.

What I’d like to do is create a few nearly identical post pages like this, but on those pages, I’d like to toggle on a few of my hidden categories (these pages will be for other websites, some of them have categories that are specific to them).

I’d greatly appreciate any direction I can get… basically I want to be able to create a few variations of the exact page linked to in this post, but add/remove content according to category.