The discovery of dissipative coupling leads to level attraction. It opens a new avenue to study light-matter interaction, enabling novel applications in quantum information and spintronics technologies based on its exotic features. The polaritons raised from spin-photon hybridization display coherence for the exchange of energy. The coherent and dissipative coupling between two resonances have been modeled by two oscillators with different coupling components, with different behaviors in eigenspace. We briefly introduced numerical methods to obtain the field distribution of resonant modes from Maxwell's equations and the time-domain analysis on the coherent and dissipative coupled system. These numerical results help us to enhance our understanding from another perspective and may benefit the future cavity magnonics research in the nonlinear regime. The level attraction is demonstrated on a planar structure by using a cross-shaped microstrip resonator and split-ring resonators. The dissipatively coupled metamaterial has been achieved by compensating the electric and magnetic coupling. Furthermore, the zero dampings in the hybridized system have been proven to be singularities. This system preserves an infinity quality factor and a sharp transition from rigorous zero to unity transmission, which displays promising applications on sensing and switch devices. Based on previous research, the interference between the coherent and dissipative coupling displays a giant nonreciprocity in cavity magnonics. Since the bandwidth of nonreciprocity is limited by the magnon, there remains a challenge of designing broadband nonreciprocal devices for practical applications. By locally control the radiation of magnon, an effective broadband nonreciprocity has been demonstrated with a few hundreds of times of magnon bandwidth. This thesis work improves the understanding of coherent and dissipative coupled systems. Moreover, it explores the approaches to implementing dissipative coupling for practical applications in quantum information technologies and cavity spintronics.