schedule c self employed business that I am stopping.

I have a small farm management business that I will not continue with after 2020.  Not selling, just stopping.  I had a small amount of income and expense for 2020 that I have entered into my Turbo Tax software.  How do I stop the business for 2021?  Do I stop it on December 31, 2020 or Jan. 1 2021 when I file for 2021  taxes.  I have zero items that I depreciate on a schedule, but I do claim a few miles on a vehicle.  

thanks in advance.