The default Drupal front page that you use "does not filter by language in any way" [source]. When using content translation (aka "node translation": one node per language version), Drupal would list all language versions of all your nodes in the default Drupal front page's feed.
So perhaps you are simply not seeing the English nodes listed as they are omitted or paged to a second page?
If you want your single content item on the front page, shown in your English default language by default, you can simply put your content item's path into the "Default front page" field at /admin/config/system/site-information.
However, that will mean that the language switcher does not work for this content on the front page (except maybe when using entity translation). So instead, I recommend to follow this answer, which will make the language switcher work on the front page even with node translation.