The first payment isn't due until Dec31, 2021.
IRS self employment tax deferred info
https://www.irs.gov/newsroom/how-self-employed-individuals-and-household-employers-repay-deferred-so...
And see (starting with question 18)
https://www.irs.gov/newsroom/deferral-of-employment-tax-deposits-and-payments-through-december-31-20...
Check if you have a Schedule 3 line 12e which goes to 1040 line 13.
See 1040 instuctions page 104 for schedule 3 line 12e SE tax deferral
https://www.irs.gov/pub/irs-pdf/i1040gi.pdf
