All applicants, regardless of age, applying for a non-immigrant visa are required to submit the Nonimmigrant Visa Electronic Application, Form DS-160. After completing the DS-160, you must print the confirmation page. This page should contain a bar code which you will have to bring with you to the interview.
Please visit https://ceac.state.gov/genniv/ to electronically complete DS-160.

IMPORTANT NOTE: If the online application is not fully completed, you will be requested to complete the application and return for a second interview.

For more information, please visit the U.S. Embassy's website by clicking here