A form from Treasury Direct cannot be imported using TurboTax. You will have to enter the Form 1099-INT manually.
To report interest income received -
Click on Federal Taxes (Personal using Home & Business)
Click on Wages and Income (Personal Income using Home & Business)
Click on I'll choose what I work on
Investments and Savings
On Interest on 1099-INT, click on the start or update button
Or enter interest income in the Search box locate in the upper right of the program screen. Click on Jump to interest income
On the screen Did you have investment income in 2023? Click on Yes
On the screen Let's import your tax info, click on Enter a different way
On the screen OK, let's start with one investment type, click on Interest and Continue
On the screen How would you like to upload your 1099-INT? Click on Type it in myself