Since the business really wasn't yours to run in 2018, you don't have to enter it on your 2018 return.
If you will be running it as a sole proprietor you will report the income and expenses on a Schedule C in your 2019 return. To do this you will need either TurboTax Self-Employed (online) or TurboTax Home & Business (CD/download).
Good luck with the business!
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