A following is a group of fans. The Beatles had a huge following. Following also means “coming after.” Rabid fans were always following the Fab Four around.
To follow is to go after, like a groupie following a rock star or a panic following an explosion. If you’re watching a TV show, when it’s over you might watch the following show. Also, a following is a bunch of people who follow someone in the sense of believing in them. The movie Blade Runner has a cult following. Sometimes when store clerks want to sound fancy, they say they can help the “following guest” when “next guest” would do.