Hello, I started a small business, sole proprietorship LLC. Do I amend my personal tax return to add this or is there a separate form I should file? What is the form?

Yes - amend your personal tax return to include Schedule C -  Profit or Loss from Business.  To do this you will need to use the Premier or Self-Employed [Home & Business for CD/Download] versions of TurboTax.

For instructions on amending your 2018 return please see the following FAQ:

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