I moved this to Offtopik because it has nothing to do with CompoJoom
but it's still Joomla related and, hey, i'm a helpful guy!
Well the Simple Image Gallery PRO is premium and I dont own a copy so I can't help too much, but take a look here:
demo.joomlaworks.gr/content/view/36/50/
Specifcially, check this:
Use for example {gallery}myphotos{/gallery} inside the article in which you want to display an image gallery of photos uploaded to the folder "myphotos". The plugin will then "automagically" present this folder as an image gallery, in a stylish thumbnail grid with "lightbox" like popups to showcase the original images, when users click on the thumbnails!
Basically, you create a new folder on your webhost - you will have to get to the cPanel access or use FTP, GoDaddy Support can guide you through that.
Then create a new folder, say "article12" under the public_html/ folder, add your photo's there, then put {gallery}article12{/gallery} inside the article somewhere. Simple as that! [This is wrong, see the 'Update' part at the end of this post]
The plugin should have a manual or documentation with it. You should probably ask JoomlaWorks for more help if you need it. But if you want to only add one photo to your article, just use the Image Upload button in the Article Editor - you won't need the plugin if you just want one picture. Hope that helped!
Update: Everything you need to know is right here -
www.joomlaworks.gr/content/view/51/41/