Template not loading properly – Shows site index list on left side

When loading the page template, I get a search box on the top left, followed by a page directory of the entire site down the left side, and the Eventbrite events load vertically on the right quarter of the page.

I’m working with an older custom theme that is likely not optimized to handle the Eventbrite API. Can anyone tell me how to edit the Eventbrite page template to make the page load properly?

Thank you!

The page I need help with: [log in to see the link]