You can choose to only show the featured image of a post in index views, but not on the post itself. That means the featured image will show on your blog, in blog posts galleries and lists, but not in the post itself. You can have a different image showing in the post (by adding it to the content like the example below).
#1 As you see on the left, I added my a different image as ANOTHER image on the left inside the content of my blog post instead of having my featured image show up at the top across my blog post as it would normally.
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