Complex sentence: According to the Constitution of India, Administration of Daman and Diu is carried out by an Administrator, appointed by the President of India as an agent of the President, not a head of state/government or a governor.
Split into simpler sentences: According to the Constitution of India, Administration of Daman and Diu is carried out by an Administrator appointed by the President of India. An Administrator is an agent of the President, not a head of state or a governor.