Coastal Communities Ocean Acidification Act of 2023 This bill requires the National Oceanic and Atmospheric Administration (NOAA) and the Ocean Acidification Advisory Board to collaborate with various entities affected by ocean acidification and coastal acidification (i.e., the decrease in pH and changes in water chemistry of certain bodies of water and waterways). Specifically, NOAA's Ocean Acidification Program must collaborate with state, local, and tribal entities that are conducting or have completed community vulnerability assessments, research planning, or climate action plans related to ocean and coastal acidification and their impacts on coastal communities. The program must (1) support collaborative interagency relationships and information sharing involving state, local, and tribal entities; (2) assist these entities in improving their existing programs to better address ocean and coastal acidification; and (3) assist these entities in identifying whether other communities can use these activities as a model. The bill also requires the Ocean Acidification Advisory Board to include two representatives from Indian tribes, tribal organizations, and tribal consortia that are affected by ocean and coastal acidification.