If you received a Form 1099-NEC with wages that should've been reported on a W-2, enter your 1099-NEC as instructed. We'll ask you questions to determine the amount of the Medicare and Social Security taxes that should've been collected as an employee. Form 8919 Uncollected Social Security and Medicare Tax on Wages
If you have a 1099-NEC that is not self-employment income subject to self-employment taxes, you need to enter the income in Box 3 of a 1099-MISC instead of Box 1 of the 1099-NEC. If your income is not self-employment income, you do not need to use Schedule C to report business income. Instead, the 1099-MISC income will go onto Line 8 of Schedule 1 as Other Income that is only subject to regular tax and not subject to self-employment taxes.
However, you should have the payer issue a 1099-MISC to you and have the amount put in Box 3 of the 1099-MISC as Other Income instead of Box 1 of the 1099-NEC as Nonemployee Compensation. Otherwise the IRS will expect you to report the Box 1 nonemployee compensation on Schedule C, Schedule F, or Form 4835 and pay self-employment taxes on it.