You would enter the wash sale amount in Box 1G that was reported to you by your broker. The adjustment code for wash sales is just a "W". You would need to select that code and then proceed through the remaining questions.
The question is not about how to enter the wash sale. I uploaded the 1099-B into Turbo-Tax from Fidelity. it is picking up this 1g amount, but next to it is a net amount, which is not picked up by Turbo-Tax. (May be Fidelity should not have mentioned anything in 1g, if in that 30 days+- period, there is no activity and wash sale is net loss.) for now, I am removing this 1g amount in turbo tax by editing it. Do not know if that is the right way of doing it.