Most of the time you'll probably just work with the form submissions in the Umbraco back office. But once in a while you might want to use the form submissions in frontend, and Form Editor offers several options for that.
You can get the form submissions if you'd like to list them - read more.
You can access statistics for the form submissions if you've enabled it - read more.
You can load a form submission and edit the submitted values - read more.