if you like to hide the picture in the actual post. I have looked at the HTML view of the post and I can see the location of the image but I have no idea how to hide it on the single post view but allow it to still be visible in the other places that it is used (background and list of posts for example)
Method 1: Add the red code adter the <img
<img style="display: none;" ........
Method 2: Add the red code brafore the <img .. and after the </img>
<div style="display: none;">
<img .............................. </img>
</div>
Method 3: Use this metod if you need to hide the images in all posts
Go to your dashboard https://www.blogger.com -> Theme tab --> Customize --> Advanced --> click on that little triangle next to "Body" / "Page Text" to open a scrollable menu --> select "Add CSS" (at the end) --> Add custom CSS - paste the red code there --> save changes
.post-body div:first-of-type img {
display: none;
}