Yes, face masks can help slow the spread of COVID-19, especially if they are combined with other preventative measures such as vaccination, frequent hand-washing, and social distancing. The US Center for Disease Control and Prevention (CDC) recommends that people wear masks both in public areas as well as in closed spaces.
Make sure to clean your hands before and after you touch your mask and while wearing it make sure that it covers your mouth, nose, and chin. Store your mask in a clean plastic bag and wash it every day if it is reusable. Also, don't use masks with valves.