Glycemic index

I’m new to scholars. I’m following the overeating class, which I love, and have a question about the no sugar no flour food that you recommend. I’m familiar with the need of lowering and keeping insulin down from the glycemic index. I’m therefore curious about potatoes that are part of your recommended food but are classified as a high glycemic index. Also wondering about the wholemeal or integral flour that you don’t recommend but that include the “grain/fiber part” and that are supposed to have a medium glycemic index. What about buckwheat flour? What about almonds and peanut? Can you please clarify so I get my protocol right? thank you very much for your help!!!