If you want an entire page dedicated to your freebie offer, then a Landing Page is the way to go, but you can also use a Form if you want to include it on one of your webpages. Both are used to gather subscribers and deliver incentive (confirmation) emails and freebies. This article22 explains the differences between the two.
May I ask what platform you are using for your website? If you're using WordPress, then you can set up a page on your site that your Landing Page will sit on. If you're not using WordPress, then your Landing Page will be a stand alone page that you can direct people to from your site. Let me know and I'll link you to the proper resources!
To get started, here's a few: