Did you apply for "logistics team member?" If so, you will be helping unload the truck and stocking the store. Wear comfortable shoes and lightweight clothing. Your training will probably be pretty basic "this goes here because the label says that right there" and you'll just have to ask questions as you come across anything that wasn't yet covered.
I don't know what "it" is that says your stardard hours is 20. Could be the amount of hours they expect to be scheduling you each week after your training schedule
The Position Acceptance Sheet lists me as Standard Hours at 20. Also I'm Flow Team