At this time you cannot import full sites into Webflow. Yes, you can export your site’s static HTML, CSS, JS and images, but thats good for when you want to host your site somewhere else.
If you only need one site, I would suggest staying with the Starter (free) plan. Then add-on a hosting subscription to it to unlock more features (like up to 80 static pages and up to 2,000 dynamic items).
Hosting is either $15/month for basic or $20/month for CMS.
Basic Hosting gives you the ability to point a custom domain to your Webflow site and have it securely stored on Amazon Web Servers and delivered over the Fastly Network.
CMS Hosting provides everything Basic Hosting does, plus a fully functional database for storing dynamic content and access to the Editor, which lets you update existing content and create new content right on your live website.
No Import SUCK! Means I have to manually tweak changes that is an editor can all be done with one or two keystrokes. This makes your tool useless after the first pass of editing!