Ministers are appointed by the President on the advise of the Prime Minister.The Ministers are usually from the party or the coalition that has the majority in the Lok Sabha. The Ministers have to be elected to the Parliament.
Composition of Council of Ministers:
a. It includes the cabinet ministers who are the top-level leaders of the ruling party or parties who are in charge of the major ministries. Cabinet ministers who are in charge of major ministries and take important decisions related to those ministries.
The Council of Ministers has a whole rarely meets as it is not practical for the whole body to meet and decide on policy matters, thus it is the Cabinet who takes all important policy decisions on behalf of the Council of Ministers.Once cabinet has made a decision, all ministers must publicly support and defend that decision, regardless of their personal views on the subject
b. Ministers of State with independent charge are usually in-charge of smaller Ministries. They at times are part of the cabinet meetings.
c. Ministers of State are attached and assist Cabinet Ministers.