Creating A New Feature Like "Posts"

I’m doing a contract I need to create a feature on an existing WP site that functions almost exactly like Posts, but has custom fields (note, I can’t use Posts as the client is already using it for their Blog).

Basically, I want to have a menu option on the side of the wp-admin called “Features”. When you click that, it opens up a summary of all the “features” that already exist (exactly like “Posts”). You can create a feature, or edit an existing one. The fields to fill are a title, date (maybe), name, body, preview, image link, and external link; nothing more, nothing less. Then I will have a template that renders out that content in a defined way, and another page that lists all of the features showing just the title, preview and image in reverse-chronological order (newest on top).

Is this something that I can do with just a normal installation of WordPress? Is there a plugin that exists that will do this for me? Do I need to develop my own plugin?

Any help would be appreciated, thanks.