Forgot to do estimated taxes for 2020, already filed for 2019

Hi,

Is there a way to go back into my 2019 tax return in order to calculate and submit estimated tax payments for 1099 income in 2020? I can't seem to find this as an option on my TurboTax when I go to "amend my return" (Mac, Home & Business edition). I completely forgot to do this and have already filed my 2019 tax refund. Thank you!