The key to becoming a columnist is a flair for writing well. What you write should be able to capture a reader's attention. Whether you go for a Journalism course or Mass communication, the most important thing is that you should have an keen interest for information/news, an eye for data and how it can be interpreted and if a story can be made out of it.

Hey!
Good career choice Rizwan! Now, as you have decided to become a Columnist, you must be knowing who a columnist is, what role does s/he play and what the responsibilities are. Just to add-on a bit, a columnist is a writer who writes for a particular publication. This piece he writes is basically a non-judgmental/biased Opinion or a Commentary on certain news or happening.
Now, answering to your query of What to pursue to became a Columnist, go for a Degree in Journalism.
Since you have not mentioned your education level (UG or PG), let me give an idea about both. If you'll be starting with your graduation, you can go for a Bachelors programme in Journalism or a Bachelor's programme in Journalism and Mass Communication. This is offered by many top colleges across India. Anyone with a passed HSC in any stream can apply for admissions. There's a college level entrance test, in which you have to appear, and then a personal interview. Some of the institutes are,
1. Delhi School of Journalism
2. GGS IPU
3. Amity University
4. Ajeenkya DY Patil University, Pune
5. Symbiosis centre for media and Communication
6. Christ University, Bengaluru


If you are looking for PG programme to become a Columnist, go for a specialised degree in Journalism. This degree will  introduce you to various journalistic platforms and processes, including professional skills such as how to work in a newsroom, how to find sources and how to present a story to the public. Some of the institutes/university are,
1. Asian College of Journalism (ACJ)
2. Indian Institute of Mass Communication (IIMC) Delhi
3. Jamia Millia Islamia
You can check additional details here- https://media.careers360.com/articles/top-mass-communication-courses-in-india
Hope this helps!