You're the one erroneously claiming that Congress has oversight authority over the president. I'm pointing out that you're wrong.
Here's Article 1, use it to prove me wrong.
https://www.law.cornell.edu/constitution/articlei
All of Section 8 as follows:
The Congress shall have power to lay and collect taxes, duties, imposts and excises, to pay the debts and provide for the common defense and general welfare of the United States; but all duties, imposts and excises shall be uniform throughout the United States;
To borrow money on the credit of the United States;
To regulate commerce with foreign nations, and among the several states, and with the Indian tribes;
To establish a uniform rule of naturalization, and uniform laws on the subject of bankruptcies throughout the United States;
To coin money, regulate the value thereof, and of foreign coin, and fix the standard of weights and measures;
To provide for the punishment of counterfeiting the securities and current coin of the United States;
To establish post offices and post roads;
To promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries;
To constitute tribunals inferior to the Supreme Court;
To define and punish piracies and felonies committed on the high seas, and offenses against the law of nations;
To declare war, grant letters of marque and reprisal, and make rules concerning captures on land and water;
To raise and support armies, but no appropriation of money to that use shall be for a longer term than two years;
To provide and maintain a navy;
To make rules for the government and regulation of the land and naval forces;
To provide for calling forth the militia to execute the laws of the union, suppress insurrections and repel invasions;
To provide for organizing, arming, and disciplining, the militia, and for governing such part of them as may be employed in the service of the United States, reserving to the states respectively, the appointment of the officers, and the authority of training the militia according to the discipline prescribed by Congress;
To exercise exclusive legislation in all cases whatsoever, over such District (not exceeding ten miles square) as may, by cession of particular states, and the acceptance of Congress, become the seat of the government of the United States, and to exercise like authority over all places purchased by the consent of the legislature of the state in which the same shall be, for the erection of forts, magazines, arsenals, dockyards, and other needful buildings;--And
To make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this Constitution in the government of the United States, or in any department or officer thereof.
U.S. Constitution
Although the U.S. Constitution grants no formal, express authority to oversee or investigate the executive or program administration, oversight is implied in Congress’s array of enumerated powers.[8] The legislature is authorized to appropriate funds; raise and support armies; provide for and maintain a navy; declare war; provide for organizing and calling forth the national guard; regulate interstate and foreign commerce; establish post offices and post roads; advise and consent on treaties and presidential nominations (Senate); and impeach (House) and try (Senate) the President, Vice President, and civil officers for treason, bribery, or other high crimes and misdemeanors. Reinforcing these powers is Congress’s broad authority “to make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof”.
The authority to oversee derives from these constitutional powers. Congress could not carry them out reasonably or responsibly without knowing what the executive is doing; how programs are being administered, by whom, and at what cost; and whether officials are obeying the law and complying with legislative intent. The Supreme Court has legitimated Congress’s investigative power, subject to constitutional safeguards for civil liberties. In 1927, the Court found that, in investigating the administration of the Department of Justice, Congress was considering a subject “on which legislation could be had or would be materially aided by the information which the investigation was calculated to elicit”.
Learn to read. It will do wonders for your DP inputs.
The Congress has appropriations and authorization controls over the Executive. They cannot execute them without knowing what the Executive is doing. The Executive includes the President.