Plot[Gamma[x], {x, -4.5, 3}, PlotRange -> {-5, 3}, AxesLabel -> {"x", "Γ(x)"}]

Plot3D[Abs[Gamma[x + I y]], {x, -3.5, 4}, {y, -2, 2}, PlotRange -> {0, 7}, AxesLabel -> {"x", "y", "|Γ(z)|"}]