reminds me of all the diapers I've folded. My mother made square diapers out of flannel. To fold them, lay flat with one corner towards you. Bring the side corners together so that the width is the width that will fit your baby. Then bring the bottom corner up and the top coarner down. For night time she doubled the diapers. This was before disposable diapers.
I've also folded diapers that have layers sewn in and they're oblong. When the baby is small, turn the outer edges in towards the center. Fold the top and bottom edges towards the center until the diaper is the correct length to fit your baby.
As an adult I made shaped diapers out of flannel. The shape is sort of like a dumb bell shape. We called the soakers. We put extra fabric in the middle. A couple of my friends preferred these. They used an outer covering too and I've seen those at thrift stores. They're fabric with a waterproof lining that breathes.
I don't know about prefolded diapers.
As to cloth covers, I found them on the Internet when my first grandchild was born. We used disposable diapers thinking that they were not only the easiest but also the cheapest. To find that actual price of the cloth diapers you need to count in the cost of laudering them (heating water, detergent, electricity to run washer, wear and tear on washer, bleach, etc.
There are now disposable diapers that break down in the landfill.