Okay, first one is I am trying to add this image to my shop. 
please note this is my image. I created it, so please do not steal it.
I used the code:
All it did was display that the image was broke, so can someone please tell me what I am doing wrong.
Now that, that is out of the way I also wanted to say I am looking for someone to coach me with coding, and more advanced use of Gimp2.8. I am not new to coding, but it has been several years since I have done them.
Anyone interested in helping me?
I can help with the first! You have the imgur URL instead of the image one. 
I don't know jack-crap about Gimp 2.8, but I'd be happy to help with any coding questions!
I did the and it still says the image is broken.
Also I wanted to say, what if I made a few graphics, or signs, or whatever, would you be able to code them for me?
There doesn't appear to be anything with your coding or your image file (although going to point out, the URL ID of the one in your original post is MaKNI7Y rather than EwnE90D). Subeta breaks the image if you use either CSS or HTML, and it's not the only image that it breaks. This honestly appears to be an issue on their end rather than yours. Their shop layout coding seems to be rather finicky and will screw it up if you edit / submit the shop coding as well.
[box=#444342]