TurboTax does not assess penalties; the IRS and state tax authorities assess penalties. Are you referring to an underpayment penalty on your balance due?
According to the IRS:
Generally, most taxpayers will avoid this penalty if they either owe less than $1,000 in tax after subtracting their withholding and refundable credits, or if they paid withholding and estimated tax of at least 90% of the tax for the current year or 100% of the tax shown on the return for the prior year, whichever is smaller.
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the IRS does not assess interest on an underpayment of tax penalty unless the entire balance due, if any, isn't paid by 7/15/2020. if you had a stare return, that might have been due at an earlier date. Not all states extended the due date to 7/15. so now if you owe you have penalties and interest on the late payment.