“Post” to “category” page?

Hi,
is it possible to change a “post” to a “category” page?

For instance I have some posts:
“best jackets”
“best denim jackets”
“best leather jackets”
all under the category “jackets”.

But I want to make the “best jackets” post into a category.

So that “best denim jackets” and “best leather jackets” fall into the category “best jackets” and the page “best jackets” shows its own article plus related links to all articles in the same category at the bottom.