Assuming you have a home business loss, or you had one the previous year, a carryforward amount is going to be on the bottom of form 8995 Qualified Business Income Deduction Simplified Computation. At least, mine is. Mine lists, on line 2, the total loss from 2019. Line 3 has the loss from 2018. THEN, on line 16, it lists the carry forward amount that will be carried forward to my 2020 taxes.
I'm not an expert, but my best guess is that you'd enter the amount on line 16 on form 3800.
