Rattlesnakes are not found in India they are exclusively found in South Western United States and get lesser in number as they extend in east, south and east. Although their bite can be fatal to humans but you don't need to worry about it because they are not found in India.
No. They are only found in North and South America.
Yes you can in the western part
That's right you won't find rattlesnakes in India, but you will find Cobras and many other poisonous snakes.