Cash App is similar to a bank account. You receive payments in your Cash App account from various sources. The income is not from Cash App itself. It's from whoever sent you the payment. How you report it depends on what the payment was for, so various payments that you received might go in different places on your tax return.
Your Cash App account might also pay you interest. If so, you have to report that as interest income. They should send you a Form 1099-INT, which you enter in TurboTax.
You might also get other tax forms from Cash App. According to an FAQ on the Cash App web site, you have to get the tax forms from your Cash App Dashboard. They do not send the tax forms to you in the mail. How you report them on your tax return depends on what type of form it is.