Hello Ritu.

There's nothing like necessary course after HS. You should pursue that course in which you are interested the most. Interest is the biggest factor in choosing the courses. Otherwise, you will regret your choice in your whole life.

So, whatever course in which you have the utmost interest, that course is the "necessary course", you should pursue that course.

if you still have any doubts or queries, feel free to ask.

Thank you and all the best for your future.