The specific credentials of the US Congress as set out in Sec. 8 Art. I of the Constitution, as well as amendment XVI to the Constitution, are assigned to the Congress as a single integral body without delimitation by house. These powers are exercised through the adoption of laws and other acts with the formally identical but separate participation of the chambers. The competence of the US Congress covers a number of areas of its activities.
Through the U.S. Constitution (Article 111, Sec. 1) the U.S. Congress has the power to establish “inferior courts” for hearing cases arising from federal law. To this end, Congress has established district courts.
Its important to understand the House of Representatives and Senate because passing legislation requires the agreement/approval of both the House and the Senate.