Fixed background on mobile

Hello everyone, I’m trying to figure out how to have different fixed image backgrounds as you scroll through a page. I found the workaround for creating a fixed div with an image but I’m trying to figure out a way to have different backgrounds like the following link:

http://www.keauhoulane.com


Here is my site Read-Only: LINK
(how to share your site Read-Only link)

Can you send you share link, plz?