OK, sorry for my confusion. You're right, you are referring to an automatically generated email, hence me not having a clue lol. So regarding the Store's platforms, there are a few different platforms and to choose from that are based on price and design, you can see more detail here Link hidden: Login to view
In regards to what you would need, apart from the subscription fee of course. You would need to stock it, so yes, you would certainly need to have your supply resources sorted, be them dropshipping, wholesale or what ever your preference would be. If you're going the route of developing you're own store, then you really should try to make the most of it by having a very healthy sock profile for customers to choose from, at least that is my opinion.
There are a few important key things you need to get right, stock profile being one, but traffic flow being another. Having your own website is great and I think what every online seller should ultimately be aspiring to if they want long term success, but getting the traffic flow is probably the hardest thing to obtain out of everything.
It's great having a well stocked online platform, but if no one is coming through the door, then no one even has a chance of buying anything and all your time, money and effort is just sitting there gathering dust in cyberspace. So you need to develop and clear and possible plan on how to generate that traffic flow before anything at all in my opinion.