Thank you for your question.
First, make sure you checked off "Business (Goods Sold)" instead of "Professional services". That makes it so that you are entering business income and not professional income. After that, follow these instructions:
1) Click on "Find" on the top right of your screen and type in Self-Employment
2) When asked if you have self-employed income and/or expenses to report, click yes
3) Input your basic business information (Business Name, Fiscal Period, Business Address, Industry code, etc.)
4) Clarify if your business has partners or earns income from websites and/or web pages
5) Enter your business income under "Business (Goods Sold)"
If you have any questions, you can contact our phone support team or contact us via private chat on Facebook or Twitter.