I received $600 for opening a brokerage account with Merrill Lynch. It shows that $600 to be entered on Schedule 1, line 21. How do I get this done?

Did you get a 1099-MISC?

You can enter the income in TurboTax as Miscellaneous Income, which is reported on Schedule 1, line 21 of the 1040 and will not generate Schedule C or SE tax.  Please use the following steps:

1. Click on Federal > Income & Expenses.
2. Scroll down to the Less Common Income section. 
3. Click on the Start/Revisit box next Miscellaneous Income, 1099-A, 1099-C.   
4. On the next screen Let's Work an Any Miscellaneous Income  click on the Start/Update button next to Other Reportable Income.
5. On the screen, Any Other Taxable Income? click the Yes box
6. On the next screen, enter the description and amount of the income.

The income will appear on Schedule 1, line 21.