To enter the US, all children, including infants, need his/her own valid travel document/passport and visa. You will need to file a DS-160 and pay the applicable fee. Generally, children under 14 do not need to appear for an interview. The website of the US Consulate that serves your country or area should have the specifics.
If you’re planning on travelling as a family creating a group application makes sense. When you select “Email Confirmation” on your Confirmation Page, you will be directed to a “Thank You” page. On the “Thank You” page you will see an option to create a family or group application. When you select this option, certain information from your application, such as destination, will automatically be imported to and displayed on a new application. The data automatically populated by the system can be amended eg if one of the applicants has a different family name or nationality, you can alter that data before submitting the application. You must create an individual application for each family member.
Source: FAQs https://travel.state.gov/content/travel/en/us-visas/visa-information-resources/forms/ds-160-online-nonimmigrant-visa-application/ds-160-faqs.html