Code T means the administrator doesn't know whether the Roth IRA met the '5 year rule', but if you parents died in 2014 and you cashed out in 2019, the rule has been met.
(the rule is the income generated within the Roth IRA is taxable if the ACCOUNT hasn't been established for 5 years. But on any day of the year you open the account, it's assumed it was opened on January 1. So worst case, your parents opened this account on 1/1/14 so you meet the 5 year rule as of 1/1/19). most probably, they opened the account before 2014, but it's a moot point now.
The taxable distribution box should be set to zero and reported on your tax return. There will be no impact on your return.
