If someone wants to make money in the field of writing in India, is it better to be an editor or to become a full-time freelance writer?

Money comes with performance and experience, both for editorial and freelance work.

Start by gaining and showcasing your experience.

If you’re a fresher, become a content writer and eventually an editor (1–2 years of work experience), gain experience with web content writing and SEO (people that hire freelancers don't want just any writing but SEO-friendly writing).

All the while create a portfolio of everything you’ve written publicly. Yes, you can include your academic assignments. Use a free site like Wix or Blogspot so you can stick this link later on your freelancer profile.

While you’re working professionally as a content writer, make a note of your performance (this goes on your LinkedIn and freelancer profile under bio or work experience). Make note of key performance indicators for good content (SERP ranking, website visitors, subscribers, etc). Add trackers to your work’s links to measure the analytics of it.

Once you have 2–4 years experience and a great portfolio, start freelancing full time with the goal of earning. Of course, you don’t have to wait to quit your job to start this. You can make a profile right now and take up easier gigs to build your reputation.

You can also earn money with writing in India with a blog. You’ll have to handle all the SEO and publishing yourself so experience helps!

Good luck.