You would post business expenses and income on a Schedule C Profit and Loss from Business.
Here is a good link to show the where to post and how: For TurboTax Online
Where do I enter my self-employment business expenses, like home office, vehicle mileage, and supplies?
If you are using Desktop: How to post on TurboTax Desktop
What can you deduct? What self-employed expenses can I deduct?
Thank you for your question.