Can this be made as a plugin ?

Hello,

when building a blog,sometimes a miss some features that I would like add and one I will try to describe. I could find plugin for it to use,so wondering if this can be made as plugin or it has to implemented into theme. As an example site I will use mybegin.com. If you click on any of the post and scroll down you can see “Photos of the” something, it looks like a gallery, once you click on the image you get redirected to a post. Wondering is there any plugin that could do it or how this is done.