Molecular dynamics simulations were employed to elucidate the tribological properties and deformation mechanisms of FeCrNi medium entropy alloy (MEA) via combined nanoindentation and nanoscratch methodologies. Nanoindentation revealed hardness variations conforming to the indentation size effect, nonlinear elastic recovery decay, and plastic work dominance at greater depths, driven by Shockley partial dislocation nucleation and stacking fault proliferation. Nanoscratch simulations demonstrated scratch speed-insensitive wear morphology, whereas depth and temperature significantly altered wear features and wear atom counts. Correlations between frictional forces, dislocation dynamics, and energy barrier transitions were established. Characterization of wear atom kinematics under diverse conditions provides critical insights for optimizing MEA applications in advanced manufacturing.