couple problems i see
1) the desriptions you are entering are far too long:
$ATC_itemDescription = "This is the second chapter in Edition 00128 of the M2 Online Learning series. Chapter 02 is based on the digital landscape of pro dSLR cameras. The HD movie has a 0:36:25 runtime and is available in 480, 720, and 1080 resolutions and mp4 and mov formats. The package includes a 21-page companion PDF of what's covered in the movie, plus a 7-page PDF reference which charts the specs of pro dSLR cameras from Canon, Nikon, and Sony. These are not streaming materials. They're yours to download and keep for your ongoing reference library.";// column binding
the descriptions that are sent to the cart should be a short description, in actual fact, description is optional. but keep it bellow 127 characters. more in the 50 character range and avoid special characters like quotes or other symbols.
2) the form tag for the add to cart form is deleted. only the input fields are on the page. input fields cannot work without the form tag.
It's not essential to set the add to cart to redirect to another page, but if you want to show the cart contents after the cart button is pressed, you can add a redirect to the redirect after setting. It's up to you as the developer to use the tool to give the desired user experience.
yes, the other pages like confirm cannot be viewed individually, they have to be viewed in context.