Also I was wondering how many potatoes grow out of one bulb is it just one per bulb like an onion or will there be multiples?
A potato tuber has several eyes. Each eye is capable of sending up a stem. If you plant the whole tuber, you may get from one to fifteen, or more, stems. When you hava a large number of stems growing in such close proximity, you get loads of new tubers, but they will mostly be small because of the competition. On the other hand if you cut the potatoes to one or two eyes per piece, you will get one or two stems from each and they will produce much larger tubers. You may get several tubers per stem.
In spite of all that has been written about covering potatoes up over and over, you only need to hill them one time. Wait until they bloom then pull 3-4 inches of soil up around the plant. The reason for doing this is so that as the tubers develop, they won't come out of the ground and turn green in the sunlight.
I reckon there are as many ways to grow a potato as there are people doing it. If you stick with it long enough, you will one day have your own style. In the meantime, you may go nuts trying to sort it all out.
Gardening at 5000 feet elevation, zone 4/5 Northern Utah, Frost free from May 25 to September 8 +/-