Explanation:

President of India is the Supreme Commander of the Indian Armed Forces.

Cabinet Committee on Security is the highest Governmental decision making body on security matters. The executive head is the Raksha Mantri, assisted by the MOD- they are the Govt while the Services are the subordinate level attached Departments of the Ministry.

Various advisory groups/committees assist the Govt/Ministry on national-security matters. The chief coordinator at PMO level is the National Security Adviser.

The highest Military professional advisory body is the Chief of Staff Committee headed by the senior most serving Service Chief viz. Chairman COSC. A C in C level (three star flag officer) heads the Integrated Defence Staff for joint-services planning under the COSC.

It is a hybrid product of the historical legacy and the subsequent evolutionary mutations to streamline higher direction of defence and country's war-making system. It is complicated and in many ways sub-optimal.