There are seven "vertical tabs" down the left-hand side of the store setting page at Store » Configuration » Store (/admin/store/settings/store). Each of these tabs contains a different group of settings. Clicking on a tab will display those settings in the main content section of the page.
This section relating to Ubercart has been modified to reflect the port from Drupal to Backdrop CMS and its usage from https://www.drupal.org/docs/7/modules/ubercart under the Share and Reuse content under the Creative Commons License, Attribution-ShareAlike 2.0