This study examines the (0⁺ → 2⁺, 2⁺ → 4⁺, and 4⁺ → 6⁺(transition levels in even-even Stannum (Sn) isotopes, ranging from (126Sn to 138Sn) (Z=50) and how effected onquadrupole deformation. By the Global Best Fit (GBF) method, calculated the electric quadrupole transition probabilities (B(E2)↑) and deformation parameters (β2) for the transitions )0⁺ → 2⁺, 2⁺ → 4⁺, and 4⁺ → 6⁺(. The investigation shows significantly minor (B(E2)↑ and β2 ) values when isotopes nearby from magic numbers, exactly the doubly magic 132Sn (N=82) for the ground-state transition. This decrease shows a reduction in collective behavior and approves a near-spherical nuclear shape at shell closures. Though, as the neutron number increases beyond the magic number, these values recover, signifying the start of collective motion driven by valence neutrons. Moreover, the results display that B(E2)↑ and β2 increase monotonically with higher transition levels for all isotopes, suggesting that collective behavior strengthens at higher angular momenta. Finally, the study confirms the strong effect of shell effects on nuclear structure and the developing form of Sn isotopes from sphere-shaped to deformed shape.