Silicene is a two-dimensional material showing high promises for nanoelectronics and thermoelectric applications due to its quantum spin Hall effect and tunable bandgap. However, a complete theoretical understanding of its fundamental properties like thermal and elastic behaviors and its comparison with graphene has remained elusive. This paper investigates the lattice dynamics, thermal conductivity, and elastic constants of Silicene. The calculations show the buckled structure of Silicene couples the out-of-plane flexural vibrations with small in-plane components breaking the planar symmetry existing in graphene. Due to weaker interatomic bonds, the acoustic phonon branches are less dispersive reducing the group velocities and thermal conductivity as compared to graphene where over 80% of heat is conveyed by the ZA flexural branch. The observed value of lattice thermal conductivity of 28.51 W/mK for Silicene agrees well with previous reports. The elastic properties including, Bulk modulus, Young's modulus, Shear modulus, and Poisson's ratio have also been evaluated to assess mechanical stability. The insights developed on the lattice dynamics and thermomechanical characteristics through this comparative assessment deepen the fundamental understanding of two-dimensional crystals for facilitating ongoing explorations focused on device applications of Silicene