Hide Feature Image

I am nearly incompetent when it comes to website construction so bear with me…all I want to do is hide the “feature image” at the top of my posts.

here is my website: asmithgraphicdesign.com

If you see my home page, there are 12 thumbnails (which are the feature images I have set). I DO want the images to appear on the home page, but once you click on the post, the feature image appears again at the top. I do NOT want the image to appear here.

How can I get that sucker out of there? Is there script I can put into each post? Is there a box I can uncheck? Can I set the opacity to 0? If it’s script I need every last bit of what I will need to copy and paste. I’ve searched all over and found plenty of script, but when I paste it into my post text, it shows up in my post as a bunch of jibberish. I used to be pretty handy with HTML, but I am lost anymore.

Thank you in advance for your help.