A set of image references and information about the images should stored in JSON format that is embedded in your script file.
When the program is loaded it should read the JSON and based on that data display the small images across the top of the screen taking up no more than 20-25% of the total screen height.
A larger (or scaled) version of the first image should also be displayed in the main section of the page underneath the small images.
Text information about the image should be displayed in a section of the page underneath the large version.
Clicking on one of the small images it should change the main display to a larger version of the clicked image along with the corresponding text.
Typing the left or right arrow keys should change the large image to the previous or next image accordingly.
Use objects in your JavaScript for each of the small images, the main image display and the contextual display.