India has 3.32 million kilometers of road network, which is the second largest in the world. Roads occupy an eminent position in transportation as they, as per the present estimate, carry nearly 65% of freight and 85% of passenger traffic. Traffic on roads is growing at a rate of 7 to 10% per annum, while the vehicle population growth, for the past few years, is of the order of 12% per annum.
If you are new to India, it is important to familiarise yourselves with rules and regulations of the roads if you wish to drive. We drive on the right side of the road, and the cars, including the rental cars are right-hand drive vehicles. All distances, speed limits (and speedometers) are in kilometers. While driving on the road, wearing of seat belts is compulsory and usage of hand-held phones is banned.
Petrol (Gas) stations are situated on both main and country roads. It is advised to fill up the tank before it starts giving warning signals, as sometimes there is a considerable distance between the towns. Indian petrol stations are not self-help. A helper will check tyre pressure, oil and water, and fill the car, and if necessary, clean the windscreen.
After the railways, surface transport is the chief means of travel in India. It is a viable option to rent a car in cities, and fares are charged on a kilometer basis. In Delhi, Mumbai, Kolkata, Chennai and other major cities, metered taxis app based taxis, as well as luxury cars are easily available on hire. There are many rent-a-car services, with prominent international companies tying up with Indian firms to provide these services. You can hire a car for a full day or for a destination.
The states and union territories of India operate their own road transport corporations and transport undertakings, which run under the care of the respective state governments. Usually, the tickets to travel on the state road transport buses have to be acquired at the ticket counters in the respective bus depots. However, many of the state road transport corporations have their own websites, which provide information to citizens about bus schedules, bus fares, bus routes, etc. and some of them even offer the facility to book tickets online. For more information about state road transport corporations and transport undertakings, and the services provided by them, click on the respective states and union territories.
Roadway covers possibilities of exploring India by Road. It explains the types of vehicles available for self drive or with driver. 

The three most common types of Tourist Vehicle given below:
Toyota Crysta Innova, Swift Dezire, Toyota Etios
Toyota Crysta Innova: Few people bring their own vehicles to India. If you do decide to bring a car or motorcycle to India it must be brought in under a carnet, a customs document guaranteeing its removal at the end of your stay. Failing to do so will be very expensive. However driving in India requires lot of patience because of extreme congestion in the cities and highways which are always busy with trucks. 
Rental: Self-drive rental in India is not wide-spread, but it is possible. If you don't feel confident about driving on Indian roads, or if self-driven rental is unavailable, it is easy to hire a car and driver, either from the local station tourist authority or privately through your hotel. By western standards the cost is quite low. In India you can get rental taxis, for nationwide.
Fuel: Petrol is expensive compared to the West and when compared to the cost of living in India  but diesel is much cheaper. Petrol is usually readily available in all large towns and along the main roads so there is no need to carry spare fuel. 

National Highway: India has one of the largest road networks of the world. The country's road network consists of Expressways, National Highways, State Highways, Major District Roads, Other District Roads, and Village Roads. The National Highways and State Highways together account for 195000-kilometer length. The National Highway comprises only 1.94% of the total length of roads but carries about 40% of the total traffic across the length and breadth of the country. 
In the Tenth Plan - 2002-2007, a large chunk is allotted for the development of the transport system namely - National Highways, State Highways and major District Roads, and Rural Roads. Under this five-year plan the completion of the National Highways Development Program (NHDP) Phase-I and Phase-II as well as elimination of deficiencies in the existing National Highway Network is envisaged.