Form 7203, Part I (S-Corp Shareholder Stock Basis), Line 6 states I need to report capital gains on Form 8949 and Schedule D. How do I do this in TurboTax online?

you would have a capital gain if distributions exceeded your basis in the S-Corp - line 6 exceeds line 5.

Turbotax does not do basis calculations so you need to enter the amount on form 1099-B worksheet. describe as "(s corp name) distribution in excess of basis". type would be C - held the stock short term - proceeds and cost basis not reported to IRS or type F - held the stock long-term. date acquired would probably be the date you started the corporation and the date sold would be the date of that distribution. proceeds from line  6 cost 0.