My very first visa application was rejected under section 214 (b).

I am doing my first year in biotechnology. I was selected in the Khorana Scholar Program headed by Indo-US. Science and Technology Forum for a three-month internship at a US university. I have enough reasons to return to India as I have to earn my Master's degree upon return to apply for higher education. My DS-2019 mentions a personal fund that will be made available to my American mentor as a scholarship. I explained that in an interview. I had no questions and did not ask for a document to show my connection to the homeland, although I bought everything from myself. What next time do I have to do to avoid rejecting the visa? Should I have provided you with all the documents, even if you did not ask for them? Please help me out