Habitable Worlds Observatory (HWO) is a large (>6 meter) ultraviolet / optical /near-infrared ultra-stable space telescope recommended by the National Academies Decadal Survey "Pathways to Discovery in Astronomy and Astrophysics for the 2020s." During the past year, the community has been actively participating in working groups that span the range of astrophysics themes to identify the driving science cases that will inform the design and architecture of HWO. In this talk, we present an overview of the Galaxy Growth Working Group activities and the key science cases identified by the various community-led sub-groups that will inform the HWO capabilities for addressing some of the most fundamental questions related to galaxy formation and evolution. Specifically, we will review science cases addressing the SMBH-Galaxy co-evolution process, the role of the circumgalactic medium in the galactic ecosystem, direct characterization of UV ionizing radiation since z = 1, and constraining the nature of dark matter properties from the small-scale galaxy power spectrum.