I mistakenly chose Turbo Tax Deluxe because I thought I would need to submit 2 states. I only need to submit 1 state, can I go back to Turbo Tax Basic?

You can downgrade your TurboTax version by using the Clear and Start Over Feature as long as you have not paid for or registered your account.

Here is a link that explains how to delete your information from TurboTax online.