Turbo says need to put 2020 Capital Gains/Loss from Sch D onto 2021 tax, but did not have Sch D in 2020. Also wants taxable income from 2020. What do I put in those areas?

Are you attempting to generate an IRS Form 2210 using the annualized income method? 

Are you referring to the screen Net Capital Gains?  If so, and if you reported no Schedule D entries on your 2020 Federal 1040 tax return, enter $0 in all the boxes.