Hi, Carol -
None of our themes include a shopping cart. This is something you will need to add with a third-party plugin. But you can use a shopping cart on any of our themes, not just the Ecommerce theme.
Here are a few shopping carts we recommend:
The last 2 I know will have video tours and examples so you can see how they work. The backend will be handled differently on each.
And I'm afraid I'm not sure what "Your Account" is referring to...if you could just clarify a bit we'll do our best to answer.