Help CenterYou may want to reverse search an image you are thinking of using, even from a website that offers free images for commercial use. Always check the license agreeement and if they do allow it, you should modify the image and make it your own.
Keep in mind that people who post an image on a website for free, generally will do it on 10, 20, 50 or more free websites. KDP will search for images online and if they see a ton of them, well they don't check licensing agreements most likely, they will just decline your book or maybe worse.
Create your own or modify one to make it your own. Then once you have reverse search that image before adding title and such on the cover if you do.
Just go to images.google.com and use this great tool.