Show one page inside another

Site URL: https://www.smifsc.com/contact

Not entirely sure how to properly phrase this question.... I have a list of links I want to embed on a page. In this case, a list of online forms (we use jotform).

On the left side of the page is a given form. On the right side I want the list of forms. My goal was to create a page with these links (i.e., a linked list) that could be updated in one place and served in a block next to each of the other form pages. 

Can see embed block (right top) doesn't work as it is just a URL.

The block below that is a markdown block, but would have to be maintained on each of the different form pages - not ideal.

Click form link in right side, form in left side will appear?

If yes, you can use Tabs Plugin.

Thank you. However, that's not what we're trying to do. The block on the right would be a static list of external forms (jotform). The goal is to serve that list (html) in the block and serving various squarespace pages, each of which contains that same block.