India has a federal parliamentary democratic governance structure. The key structures and institutions that govern India are:

• The President of India, who serves as the ceremonial head of state with limited powers related to appointments, pardons, and acting as a mediator in the event of a political crisis.
• The Prime Minister, who is the Head of Government and holds executive powers.
• The Parliament, consisting of the Lok Sabha (Lower House) and the Rajya Sabha (Upper House), which enacts laws and decides on national policy.
• The Supreme Court of India, which is the apex court of the country and acts as the final interpreter and enforcer of the Constitution and the laws of the land.
• The State Governments, which are headed by Chief Ministers and are responsible for the governance of their respective states.
• The Judiciary, which consists of various courts and tribunals at the state and national levels and is responsible for upholding the law and delivering justice.
• The Election Commission of India, which is responsible for conducting elections at all levels, from national to local government bodies.

Together, these structures and institutions form the backbone of India's governance structure, ensuring that the country remains democratic, secular and sovereign.