Have you already filed?
If you have not filed, here are the steps:
In TurboTax online,
If you have already submitted your tax return, you will have to wait until Feb 12 when the IRS opens the gate. You cannot return to the program to make any changes before that.
If your return got rejected for whatever reasons, you can return to the program to add your new form along with other changes. You do not need an amendment 1040-X.
If your return has been accepted, you will have to amend your return by filing a form 1040X. You should not try to amend your return until it has been fully processed and you have received your refund or your payment has cleared.
Beginning with the 2019 tax year, you can e-file amended tax returns. If you used TurboTax to prepare Form 1040-X, follow the software's instructions to e-file the amendment.
To see how to amend your taxes, click here:
A 1099NEC is for self employment income. You will have to upgrade to Deluxe or higher.
You can enter Self Employment Income into Online Deluxe or Premier but if you have any expenses you will have to upgrade to the Self Employed version. Or use any of the Desktop CD/Download programs.
How to enter income from Self Employment