Get your taxes done using TurboTax

You will enter your son's 1099-NEC as self-employment income on Schedule C Profit or Loss from Business.  Follow these steps to enter his personal trainer income and expenses in TurboTax. 

1. Open or continue your return
2. Search for schedule c and click the Jump to link in the search results.
3. Answer Yes to Did you have any self-employment income or expenses?
   • If you've already entered self-employment work and  this as a new business select Add another line of work
4. Follow the onscreen instructions. 

This link has information that you may find helpful when preparing your son's Schedule C Where do I enter Schedule C?

To enter the estimated taxes your son paid follow these steps:

1. Open or continue your return
2. Go to the Federal section, then Deductions & Credits
   • You can also search for estimated tax payments and select the Jump to in the search results
3. Select Estimates and Other Taxes Paid
4. Select Start or Revist next to Estimated Tax Payments
5. Choose Start next to the type of estimated tax payment you'd like to enter
6. Follow the screen prompts to enter his estimated taxes paid.

This link Where do I enter my estimated tax payments? has information you may find useful.