I want a gaming PC in 19900 INR

I'm sorry to say that you won't be doing much gaming at that price - although I don't know the cost of components in India.

My advice at that price point is to go with a pre-build PC. Manufacturers get incredible deals on their components and can put together low-end PCs far cheaper than individuals can.

Look for an AMD APU that has a reasonable graphics component. Look for web specials or maybe sales events to celebrate holidays or something along those lines.

You could also look if you can acquire an older, 2nd hand PC. You may bet considerable bang for your buck that way - just get someone who is technically competent to help you look it over so you don't get ripped off.