It's complicated, to say the least.
A good starting point is the Wikipedia page on the Law of India...
India maintains a hybrid legal system with a mixture of civil, common law and customary, Islamic ethics, or religious law within the legal framework inherited from the colonial era and various legislation first introduced by the British are still in effect in modified forms today. Since the drafting of the Indian Constitution, Indian laws also adhere to the United Nations guidelines on human rights law and the environmental law.
- Constitutional and administrative law (with the Constitution, in various languages, found here)
- Criminal law
- Contract law
- Labour law
- Company law
- Tort law
- Property law
- Tax law
- Trust law
- Family law and personal law
- Nationality law
For researching specific legislation, the India Code site is a comprehensive "Digital Repository of All Central and State Acts" and contains searchable legislation for all the above areas.
And then there's the Indian Kanoon with a large amount of caselaw from court and tribunal decisions.