Yes, you need to create a single entry with all your best work. This is taken from the main contest page:

Create an entry page that shows off ALL your best work for the selected category. Treat the contest like a job application where you want to impress a recruiter with a wide range of skills related to the industry (category).

Please take a look at some of the winning entries from previous years

You will see that they create a single entry page that shows their best work on it. They include supporting media, written descriptions, process views, and other widgets to help present themselves to the judges/recruiters on one page. It's like a summary of your portfolio, all related to the category you are entering.