Creating New Region

I'm trying to add a custom region to the Zircon theme.

I've been toying around with it for a few weeks now.

I can get the region to show up when I click "Demonstrate Block Regions" however, I get the block/view I created to show up I the region that I created. It also shows up in the block layout page, and I can add blocks to the region but again, the block/view doesn't show up in the region.

As seems to always be the case, I found a few tutorials on the web pertaining to Drupal 7 but very few pertaining to Drupal 8. In one article I came across (see article here) the first step was to edit the template.html.twig file. I can't seem to find this file or the region.html.twig file anywhere. All I could find were html.html.twig and page.html.twig . Where would I find the template.html.twig and the region.html.twig files, and do you think this is my problem?