do i need to creat an app to use this?

i’m looking for a solution to be able to share posts from my blog to my fb page but with large image on the fb post.

I’ve been reading how now facebook posts now have large images, well not on my posts?! still getting a thumnail, even when i change the image in the post to one from my desktop.

If i upload an image and put the blog post url in the post then when the image is clicked it opens as an image in fb, not linking to the post!

I’ve seen other ppls fb posts with a larger image that links to the blog post, how is this done? is this app for that… and creating an APP for it, …really?!

https://wordpress.org/plugins/facebook/