The 2020 program doesn't come out until November and Turbotax is not set up to allow partial entry during the year. If you have a business, you can track your PNL with Quickbooks and then import your information into Turbotax, but that's about it.
You can estimate your 2020 taxes by creating a dummy return with the 2019 program, or by using the Taxcaster, or the IRS tax estimator.
TaxCaster tax calculator
https://www.irs.gov/individuals/tax-withholding-estimator
