It sounds like TurboTax (TT) may be calculating self employment tax. How was his earned income reported, on a W-2, a 1099-NEC, or something else? Is the earned income on line 1 or line 8 of form 1040?
You don't add the +350, TT does that automatically when calculating his standard deduction on line 12a (& 12c) of form 1040. It does not go anywhere else.
Are the capital gains long term or short term or capital gains distributions?
