Ok, this is a naive question your mother (or more likely, your grandmother) might ask. So sue me.
In the past, there were top-40 radio stations, variety TV shows, and later MTV where you could hear the latest music. Or you could go to record stores or record departments of big stores and see/hear/buy the latest stuff.
From what channels/sources do people find out about the latest pop music now? How do people keep up with music?
(Aside: I remember going with my mother to a record store in Buffalo, NY in 1964 to buy the 45 of the Beatles’ I Want to Hold Your Hand. I had heard them on the Ed Sullivan Show and fell in love. She liked them, too, God bless her. My father didn’t like their haircuts. )