Hello Aman
All I would like to say is that the criteria for selecting a student vary from college to college. However, you should most importantly, carry all your necessary documents with you like- 10+2 pass certificates, character certificate, etc. Demanding the certificate of your extra-curricular activities completely depends on the interviewer. However, if the interviewers ask for it, you can simply say that you were not provided with any, and if they ask questions about leadership, I hope you can answer them with full confidence, as you were already accustomed to the field.
For other details about St. Stephens, visit: https://www.ststephens.edu/
Hope this was helpful!
All the best.
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