When you enter your investment sales that resulted in the long term capital loss then it will automatically be carried to Schedule D line 21 and then to Schedule 1 line 13.
Please see this FAQ on how to enter your investments sales:
https://ttlc.intuit.com/replies/5209280
Please see this FAQ if you had a capital loss carryover:
https://ttlc.intuit.com/replies/3301508
