What payment gateway did you select in the Power Store settings?
some payment gateway options will require that you enter the credit card number on the gateways server.
What have you set for shipping options in the power store settings? you need to configure the shipping type that you will offer in the shipping settings.
also, make sure to enter a weight for your products when adding the to the catalog.
if the items in the cart do not have a weight, there will not be any shipping applied.