"Small business" usually means a sole proprietorship. That is, you are a self employed person. In that case, you do not file a separate business tax return. You include your business income (and expenses) on your regular personal return (form 1040). You do so by attaching Schedule C (https://www.irs.gov/pub/irs-pdf/f1040sc.pdf).
If you are using the on line TurboTax (TT), you will need to use the "Self Employment" version. With download software, any version will work (use Deluxe or higher if you live in a state with an income tax)
