In the cosmic ecosystem, the circumgalactic medium (CGM) is a massive baryon reservoir of baryonic inflows and outflows, shaping galaxy formation and evolution. The rapid decline of star formation rate from the Cosmic Noon is crucial in defining present-day galaxy characteristics, yet its driving force remains uncertain. Characterizing and modeling the CGM provides new insights into understanding this fundamental transition in galaxy evolution. In this talk, I will review observational constraints on the multiphase CGM using multiwavelength probes. In particular, I will explore the spatial distributions of different phases, with a focus on addressing a fundamental question, do galaxies host all of their baryons within their halos? In addition, I will highlight the recent improvements in constraining the thermodynamic properties, which provide key insight into resolving the fate of gas in the CGM, either feeding galaxies, escaping, or being virialized and staying in halos for a long time.