S. RES. 2 is a resolution to notify the House of Representatives that the Senate has gathered enough members, known as a quorum, at the start of the 119th Congress's first session. This announcement allows the Senate to officially begin its legislative activities, signaling...
Simple Explanation
The Senate wants to let the House of Representatives know that they have enough members present to start their work, kind of like telling their friends that they're ready to begin playing a game together.