The second docs. You can keep one _index.md for your homepage and one in each of your content sections, taxonomies, and taxonomy terms. The following shows typical placement of an _index.md that would contain content and front matter for a posts section list page on a Hugo website:
Well well Dave, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker includi
Distribution of letters, as opposed to using ‘Content here, content here’, making it look like readable English.