Formatting for a paperback is quite different from formatting for an e-book. If you're using Word, I recommend the free Smash*words style guide. Or look for Notjohn's posts--he has a guide for Word users.
A better way, however, is to use HTML/CSS and upload an ePub file.
Covers are entirely different as well. CS has a front cover, back cover, and a spine. An e-book requires only a front cover.
If you have the Createspace cover and are reasonably skilled with a photo editing app, you could maybe crop out the front cover and use it, but it's better to design a separate one. I upload JPEG files, 1800 x 2700 pixels.
So basically it is going to take some work to make it into an ebook.
Yes, though I think it's a lot easier than formatting a handsome paperback. You might read the third post on my blog.
Another thing is, that the cover a I created on create space, can I not use it for the Kindle? How would I do that?
Yes, I've done this. I just did a screenshot of the CS cover. I think you can also download a PDF of the cover (when you're in the proofing stage) and could probably work from there. Or better yet, order a physical proof and scan the front cover.
(Don't trust KDP to publish a print edition. Don't trust CreateSpace to publish an ebook.)