Hi Vinita,
If you are a keen writer,
begin by writing a blog. This is a free tool where you control what you write, when you write and how much you write. Further the audience reach is not local but national and international.
Most important of all, by regularly writing you would have build up a data bank of writing, you would realize your strengths and limitations as a writer and if fortunate even get a good following and get noticed too.
A newspaper columnists is often someone who has established himself/ herself either as a writer or subject expert or is a renowned personality. Your blogs can help you built up those credentials. You would have to write on some specialized topic or have a focus area of writing since people would be reading your work because they have an interest in that.
You are welcome to visit the following two Motivational and Inspirational blogs that I write which will give you a perspective as to what I have elaborated above.
Actspot's Blog - Over 850 followers and 1,44,000 views
Academy for Creative Training - Over 215 followers and 42,000 views
Best Wishes