adding a comparison chart to a site page

Hi there, I’m hoping you can give me some insight into how my WP site is ‘held together’?

On some of my pages, (when logged in as Administrator) – I can edit page. However, the page (attached) only has ‘edit product category’ in the admin bar up top.

I’m actually just trying to add a comparison chart to the page (see attached screenshot). But do now know how to make it show up on this page underneath the two ‘membership products’ that are shown.

Can you tell by looking at this?