where do I put Thrift Savings Plan Gross Cash Payment , Federal Withholding and Net Cash Payment?

[emalixi]

see above.

[SabrinaD2]

To enter your Thrift Savings Plan (TSP) Gross Cash Payment, Federal Withholding, and Net Cash Payment in TurboTax, follow these steps:

1. If you have a TSP through your employer, your contribution is reported in Box 12 of your W-2 with the letter code D. TurboTax will handle the tax deduction for you.
2. Don’t re-enter your contribution in the retirement section, because it's already in your W-2.

Refer to the  Intuit's Help Page.

Reach back out if this TSP through an employer.