Article II of the U.S. Constitution establishes the Executive Branch of the federal government. The Executive Vesting Clause, in Section 1, Clause 1, provides that the federal executive power is vested in the President. Section 3 of Article II further requires the President to take Care that the Laws be faithfully executed.1 The executive power thus consists of the authority to enforce laws and to appoint the agents charged with the duty of such enforcement.2 The President also has distinct authority over foreign affairs, and alone has the power to speak or listen as a representative of the nation.3

ArtII.S4.1 Overview of Impeachment Clause
Article II, Section 4:
The President, Vice President and all civil Officers of the United States, shall be removed from Office on Impeachment for, and Conviction of, Treason, Bribery, or other high Crimes and Misdemeanors.

https://constitution.congress.gov/browse/essay/artII-1/ALDE_00000243/