Thank you for your answer.
In Turbotax Premier 2020, after transferring the info contained in the 1099R, e.g. with "10" for box 1 (Gross distribution), "5" for box 2b (Taxable amount), and "G" for box 7 (Distribution code), a window did appear asking whether the money was rolled over into a Roth 401 K or not. If I answered "yes", then the whole amount in box 2b, "5" will be taxed in the subsequent calculation, and if I answered "no", the whole amount in box 2b, "5" will not be taxed. The problem I have is that only a portion of box 2b, e.g. "3", was rolled over into a Roth 401K, and Turbotax does not have a provision for reporting correctly that fractional roll-over into a Roth 401K. I presume this is an unforeseen limitation of the Turbotax program.
