India is one of the most incredible countries of the world. It is not only the world's 7th largest country, but it is also the host for many prolific and mesmerizing locations that one must see in his or her lifetime.
So, basically what I am trying to say is that there is no right answer for this question. There are thousands of places in India and each one of them has its own charm and uniqueness. From the scenic beauty of Kashmir valley to Kanyakumari's calming beaches and from the mighty Rann of Kuchh to ever-beautiful Darjeeling, India is full of places everyone must visit at least once.
Nevertheless, coming back to your question.... If you are asking, I would suggest you to visit Kashmir for a start. It is one of the most beautiful and heavenly places in the known universe.
The beauty of Kashmir lies in the steep valleys between mighty Himalayan ranges, covered with thick vegetation of beautiful evergreen trees. Every small place like Gulmarg, Srinagar and Sheetmarg have their own specialties. And even the unknown and lesser known places such as Jai Valley and Bhadarwah gives extraordinary views that you may have never seen in your entire life.
Finally, if you are looking for the best place to visit in India, then start your quest with Kashmir. But don't let that quench your thirst as there are a lot more gems in India which are yet to be discovered by enthusiasts like you.