The group on the periodic table that contains elements that are almost completely non-reactive is known as the Noble Gases, found in Group 18.
Noble Gases, which include helium, neon, argon, krypton, xenon, and radon, are characterized by having a complete outer electron shell. This full valence shell makes them extremely stable and unreactive under standard conditions. As a result, they do not readily form chemical bonds with other elements.
While other elements may gain or lose electrons to achieve stability, Noble Gases have already achieved this state and tend to remain in their inert form. This property is what makes them uniquely non-reactive compared to other groups in the periodic table.