Remove Featured Image Thumbnails from posts

I know this is a recurring issue, but I am trying to remove the featured image thumbnail from posts and from my blog (or Latest Posts) page, but I still need to have a featured image for the Featured Image Thumbnail Grid plugin.

I am running the Adelle theme and cannot figure out where the code is to delete it from posts and pages.

Also, I am currently using a temp URL as I am in the process of switching my domain over, but I can provide it if necessary.

Can anyone help?