With a net loss there is no need to enter the Form 1099-R that you will not receive until near the end of January 2021. Just enter the original Roth IRA contribution, let TurboTax indicate how much is an excess, then enter the excess amount (not the loss-adjusted amount) as the amount of contribution returned. TurboTax will prompt you to enter an explanation of the return of contribution and that's all you need.
