You have to report all your income, no matter how little it is, whether or not you get a reporting form. You can report the winnings as "other income" on Schedule 1 line 8 with a description that you enter.
In the Search box in TurboTax type "lawsuit settlement" (without the quotes), then click the link that says "Jump to lawsuit settlement." I know that's not what you have, but it's the only search term I could find that gets you to the right place.
The first screen asks, "Any Other Taxable Income?" Click Yes.
On the next screen, "Other Taxable Income," enter a description such as "Game show prize" and enter the amount. Click Continue.
On the next screen click Done.
