There are a lot of things to take into account. You definitely needs to register your business. No question about it. A S-Corp or LLC, as far as I know S-Corp is better when starting up. There is nothing like license for most business but since it appears that you will be selling food items online, more digging is needed on license.
I have been in US for around a decade and am myself interested in starting something like that. If you are interested in seeing how we can collaborate on this kind of effort, I will be interested in talking to you. I am on east coast in US and have friends who are accountants and lawyers who will definitely be of help in starting a business like this. Let me know what you think..