To change the catalog (or product archives) layout, please go to Customize > Product catalog and click on the Layout button.
Once you expand Layout, you’ll be presented with options to change the number of products per row and column, alter the sidebar position on product archives or disable it completely and also decide if you want to show your products as a list or as a grid. You can see these options in the following image:
As far as the elements are concerned, also in Layout you will find toggles for the most important page elements, like page title and description, sorting, breadcrumbs and results count. Again, this options apply only to your main shop page and product archives.