Parallax plugin

Hi guys, I found this plugin code online seems to be a nice fit to make into a widget and could work well with elementor free. However my skill set is not enough so it seems. The coding seems very simple with CSS JS and HTML, but I can’t get it to work. Anyone care to give it a try and make a widget out of it?

https://www.cssscript.com/smooth-parallax-scroll-plugin-universal-parallax/