The TurboTax online editions for tax year will not be available until early December.
The TurboTax desktop CD/Download editions for tax year 2019 are currently available - https://turbotax.intuit.com/personal-taxes/cd-download/
You can enter your tax data as often or as little as needed at any time using TurboTax. Only you control when or if the tax return is filed.
If you earn interest on a checking or savings account then your financial institution will send you a Form 1099-INT for the interest earned during the year. That interest is to be reported on your tax return.
