how do I get a picture to appear at the top of this post?

Hi. Under Post Settings, I selected Post Template style 3. I expected the featured image to appear there, but as you can see, it is just a grey box:

How do I get an image to appear there? Also, would it have to be the featured image, or could I choose a different photo to appear up top there?

This is the specific image that I’d like to change:

I don’t have advanced knowledge of WordPress, so please explain as simply as possible! Thank you!

I asked in the general Wordpress forum and was told this might be a bug with the Theme and to contact the Theme creator about it. I hope I’m in the right place. If not, please point me in the right direction.

Hi there. I was hoping to get some help with this. Thanks for taking a look. I think there’s probably a simple solution, I just don’t know it!

@wordpress_Port If you would like me to look at it for you, I could do that but that would have to be tomorrow as it is quite late into the night here. It would also help if you gave me access to your theme so that I have a look at it.

Hi. Thanks for the offer. I don’t think I have to give you access to anything for you to help me with my problem. If I haven’t explained it clearly, I can try again.