Tidal disruption events (TDEs) are among the most fascinating astronomical phenomena, offering a unique probe into the properties of massive black holes and the nuclear environments of galaxies. In this talk, I will present results from theoretical calculations of the realistic rates of TDEs for both supermassive and intermediate-mass black holes. These results reveal how TDE rates depend on black hole mass, stellar dynamics, and galactic environments. I will also show state-of-the-art simulations of TDE accretion, outflows and emissions, demonstrating how these processes produce the diverse emission features we observe, including Bowen fluorescence lines. Finally, I will discuss the broader implications of TDEs for black hole growth, particularly in the early universe, and their role in shaping galactic evolution. By exploring these results, we can better understand the physics of TDEs and their critical role in the growth of black holes and the evolution of galaxies across cosmic time.