The Executive Branch
http://constitutioncenter.org/constitution/the-articles/article-ii-the-executive-branch This link explains the second article of the constitution.
This article explains how the president is selected through the electoral college. The electoral college is a group of people elected by the states equal to the combined number of representatives and senators in congress. The president is elected by these members, however he needs 270 of the votes in order to become a president. Otherwise, the house of representatives select who the president will be. This is called indirect democracy. We do not choose our president directly
The president and vice-president are elected at the same time and serve a 4 year term, for a maximum of two terms. In order to become eligible candidates must be natural born of the US, have lived in the US for fourteen years and be at least 35 years old. The president salary is set by Congress and cannot be modified during the term. Before assuming office the president must swear:
"I do solemnly swear (or affirm) that I will faithfully execute the Office of President of the United States, and will to the best of my Ability, preserve, protect and defend the Constitution of the United States."
Among the presidential powers, the president is commander in chief of the armed forces, he negotiates treaties and nominates justices of the supreme court. At the same time he runs executive agencies and has the power to pardon any person. Regarding signing laws and treaties, it is necessary to have a super majority agreement, that is at least two thirds of the congress must agree with the new law. This concept relates to check and balances. The president also has implied powers, that is, he can perform actions that are not stated in the constitution but that still can be legally performed.
If the president has committed high crimes and misdemeanors, he can be impeached and judged by Congress. In Congress he would need a super majority of two thirds in order to be removed from office. In the past only three presidents have been impeached: Andrew Johnson, Richard Nixon and Bill Clinton.
Impeachment of Andrew Johnson