According to the CDC (Center of Disease Control) People, including children older than 2, should wear a mask in indoor public places if they are:
Not fully vaccinated, fully vaccinated and in an area with substantial or high transmission or fully vaccinated and with weakened immune systems. In general, you do not need to wear a mask in outdoor settings. In areas with high numbers of COVID-19 cases, consider wearing a mask in crowded outdoor settings and for activities with close contact with others who are not fully vaccinated.
Correct and consistent mask use is a critical step everyone can take to prevent getting and spreading COVID-19. Masks work best when everyone wears them, but not all masks provide the same protection. When choosing a mask, look at how well it fits, how well it filters the air, and how many layers it has.