The President has the power to do things becuase he is head of the government but he also has to go through Congress and the senate before anything can become offical. he has the power top appiont new people to federal executive, diplomatic, regulatory, and judicial officers, and concluding treaties with foreign powers with the help of senate.
http://bensguide.gpo.gov/3-5/government/national/president.html
That the President is head of the executive branch and has a large part in making laws. he approves laws that congree makes or bills that the senate approves. he is alo head of the military and can send troops to where he want them to be.
http://www2.smumn.edu/deptpages/~instructtech/institutional_planning/role_president.htm
The President is the primary sponsor and initiator of the strategic planning effort. He provides leadership to executive, direction and strategic planning effort to do things right, meeting and communicating regularly with both internal and external constituents. The President is the chief spokesman articulating the value and importance of strategic planning.
Article II, section 1, of the U.S. Constitution provides that "[t]he executive Power shall be vested in a President of the United States of America. He shall hold his Office during the Term of four Years, . . . together with the Vice President, chosen for the same Term..."
the President is the person who is incharge of everything for making law to sending the military overseas.