This is a large problem. India has fascinating places to vist all over the country. There are accommodations at almost all levels everywhere. There is such astounding variety that nobody can answer such a general question.

We need to know things like,

1)how long you will spend,
2) how much you are prepared to spend,
3) how you want to travel: plane, train
4) when you plan to go.

Then we need to know more about your interests and preferences.

Some of that will help.
You might want to spend some time with a good guide book or two also.