The TurboTax online editions for tax year 2021 will not be available until sometime in early December.
The TurboTax desktop CD/Download editions for tax year 2021 are available now on this website - https://turbotax.intuit.com/personal-taxes/cd-download/
You can use the TurboTax calculator TaxCaster to get an estimate of the tax refund or taxes owed - https://turbotax.intuit.com/tax-tools/calculators/taxcaster/
