Bulk listing CSV file missing some columns?

I’m trying to upload a bulk CSV document for my products but the product description fields as well as a few other (GTIN exception reason etc.) are missing. They appear in the example tab as well as the valid values tab, but not in the template tab I need to input into.

Anyone have a lot of experience working with these inventory files or this specific issue? Also wondering about the GTIN exception as I do not sell branded products and used to list them 1 by 1 but with scaling up how does the CSV work without inputing the Product ID (GTIN) column.

Thanks for any help.