If I am understanding what everyone is asking correctly.... You want an image on your homepage that is clickable to goto a collection, product, blog, etc.... I've seen many complicated ways to do this but there's actually a VERY easy way even for people without coding experience.
Upload your image you want to use by whatever means...
Goto Files and get that image URL,
Then simply goto your homepage and add a custom content section.
Once in there, add custom HTML
and use the most basic easiest HTML for an image with link. If you don't know how to do that, just google html code for image with link.
Very simple. If you want to control the size of your image, you can then add width and height to it.