Go on the kvpy official website. In the login window, click on 'Sign in'. After you click on the next button, an option will pop out asking you for the language you need. You can choose Hindi there since the exam is available in both the languages Hindi and English.

Refer to the site below for more detailed information to give the mock tests..

https://school.careers360.com/articles/kvpy-mock-test

Best wishes. Thank you.