From my understanding, Robinhood has not made their documents accessible by TurboTax, yet. According to what I can find they make them available to Turbotax February 16th.
You should be able to enter them manually if you want to do that now.
To do that find the Tax Forms section in the Robinhood App.
That can be found under Profile (lower right; looks like a person) then menu (top left; looks like three horizontal lines) then scroll until you find Tax Center.
