You will first go to the section for wages and income. Then, you will say yes for self-employment income with a 1099-NEC. Enter your income and expenses information under self-employment Sch C income and expenses section under "mileage".
No, that should not make a difference. Just make sure that the income does go in correctly. Some people have had a problem.
The 1099-NEC was brought back for 2020 tax returns just to report non-employee compensation and the box on the 1099-MISC which used to contain that information is gone on the 1099-misc for 2020 tax
[edited 03/21/2021|3:02 pm pst]