Neutron stars are compact objects formed from massive star remnants after a core-collapse supernova and are composed of extremely dense nuclear matter. This dense matter is not well understood and makes neutron stars a rare probe into the low temperature, high density region of the QCD phase diagram. The highly dense matter present inside neutron stars contain neutrons, protons, electrons and muons, but it is also possible for exotic particles like heavy baryons like hyperons and Delta-baryons to exist. We describe this system of particles using the Relativistic Mean Field (RMF) theory which we then employ to obtain the equation of state (EoS) - a relation between the pressure and energy density of the matter. This equation of state can be used to calculate macroscopic properties of neutron stars like mass, radius, tidal deformability, etc. Observations of these properties from gravitational waves emitted during mergers of neutron stars can be used to constrain the EoS and obtain a better understanding of the composition of neutron stars. This talk will provide a comprehensive overview of the physics of neutron stars, how they can be modeled, and how we can constrain the EoS using observations from gravitational waves.