The form that is used to report the 401k withdrawal is Form 8915-E. It is not currently available.
The IRS will be releasing Form 8915-E to use with the 1099-R. Here is more information:
CARES Act and 1099-R Withdrawal.
The software has not been updated yet because the form has not been finalized by the IRS. Once the software has been updated, you will be prompted through the form with instructions on how to enter the information.
The IRS has not provided a release date for the form at this time. Use this link IRS Form Availability to watch for when the 8915-E form will be available in the software once the IRS completes it.