Generally, portfolio income is not reported on Sch E. Part I is used to report income/deductions from rental real estate and Royalty income/expenses. I interpret your comment of "Other Portfolio Income" to be investment income. Not reported on Sch E.
See Instructions for Sch E
https://www.irs.gov/pub/irs-pdf/i1040se.pdf
Link here for Investment Income and Expenses (Portfolio Income)
https://www.irs.gov/pub/irs-pdf/p550.pdf
I was specifically instructed to enter these details on schedule E (other portfolio income comes from distribution from a trust and expenses are legal fees paid by the trust). Thus my question of how to force Turbotax to enter these numbers?
Please let me know if you figured this out. "Other portfolio income" is a nightmare for Turbotax.
For 2021 tax year, Sch K-1 (1041) would be entered in Personal Income
Go down to Business Investment and Estate/Trust Income and then click on Sch K-1
Select Estates or Trust (Form 1041)
Enter all the information from the Sch K-1. For 2021, Box 5 is Other Portfolio Income
As for the expenses, they should be listed on the Sch K-1 and you may have to check the instructions for the beneficiary to determine where they go and if currently deductible.