This income is self-employed income and you have to pay self-employment tax on it. Self-employment tax is your contributions to Social Security and Medicare.
If you had expenses related to this work, you can deduct them against this income. To deduct expenses, you'll need to upgrade to TurboTax Self-Employed.
Please read this TurboTax FAQ on how to report this income:
https://ttlc.intuit.com/replies/4801198