Tax on Proposed Roth Distribution

If you are thinking about the 5 year rule, then there are two rules.    Your regular contributions to a Roth become qualified after 5 years from the time any Roth IRA is opened so distribution of your *contributions* are tax and penalty free after 5 years, however each *conversion* to a Roth has it's own 5 year clock that start on the date of the conversion.  a 2020 conversion will not be qualified until 2025.    Once you turn age 59 1/2 then there is no longer any early distribution penalty at all but the 5 year clock for taxable earnings still apply.

See IRS Pub 590B  https://www.irs.gov/publications/p590b

Distributions of conversion and certain rollover contributions within 5-year period.

If, within the 5-year period starting with the first day of your tax year in which you convert an amount from a traditional IRA or roll over an amount from a qualified retirement plan to a Roth IRA, you take a distribution from a Roth IRA, you may have to pay the 10% additional tax on early distributions. You must generally pay the 10% additional tax on any amount attributable to the part of the amount converted or rolled over (the conversion or rollover contribution) that you had to include in income (recapture amount). A separate 5-year period applies to each conversion and rollover. See Ordering Rules for Distributions , later, to determine the recapture amount, if any.