Research on the galactic ecosystem relies on high-resolution X-ray spectral observations of hot baryons (primarily in the form of plasma) with temperatures reaching millions of degrees, which are distributed around galaxies and between galaxies. The lack of such observations has become a bottleneck in the field of galaxy formation and evolution. In the recently published Pathways to Discovery in Astronomy and Astrophysics for the 2020s (Astro2020) report by the National Academy of Sciences, which outlines the astronomy and astrophysics priorities for the 2020s, the study of the galactic ecosystem, including galaxy formation and evolution, is highlighted as one of the three priority areas. The formation and evolution of galaxies in the cosmic web are also identified as a priority area in the "14th Five-Year Plan" for the Development of the National Natural Science Foundation in China. The Milky Way serves as an important template for studying galaxy formation and evolution, and it is a key focus in understanding the evolution of hot baryons in the galactic ecosystem, which is a universal problem in the neighboring universe. Research on the Milky Way forms the basis for answering the question “Whether the Milky Way is a special galaxy” among the 125 questions posed in the journal Science. The study of hot baryons in the Milky Way is also closely related to two frontier scientific questions in China's Common Frontier Science Issues in Space Astronomy: "How did the Milky Way and its neighboring galaxies form and evolve?" and "The matter cycle and interaction processes from the interstellar medium to interstellar space.