Hugo will automatically create pages for each root section that list all of the content in that section. See the documentation on section templates for details on customizing the way these pages are rendered.
Content Section vs Content Type
By default, everything created within a section will use the content type that matches the root section name. For example, Hugo will assume that posts/post-1.md has a posts content type. If you are using an archetype for your posts section, Hugo will generate front matter according to what it finds in archetypes/posts.md.