Where do I find form T657 for Capital Gains Deduction? It does not seem to be an option on the premier version.

We're happy to help you. 

To enter your Capital Gains Deductions, please follow the instructions below:

1. Sign in to your TurboTax Online account. 
2. Start your 2020 return.
3. Click on the find icon at the top-right corner of the page.
4. Please type and select the option titled "Capital Gains and Capital Gains Deduction Profile" and click " Go".
5. You'll see the page titled "Your Capital Gains Profile for 2020", and select the option that best meets your requirement.
6. Click "Continue".
7. Click on "Enter more years for your name". 
8. Now you'll be prompted to the page where you can enter the details for your T657 Form. 

Also, please review this TurboTax blog on Capital Gains Deductions.

Thank you for choosing TurboTax.