Dear aspirant hope you are doing well. Your question is whether we know hindi Or not, yes Offcourse many of intern know hindi but it's is a nation wide platform. So from South Indian people don't know hindi well but english is international language, so everyone answer in English . There is an option to translation of language from english to hindi. If there issue.

Thank you

Haa yahan jyadaa se jyadaa logon ko atahai.