Names
Using brand names and titles is not really a problem in fiction, but a little bit goes a very long way. Titles are not copyrighted, lyrics are. In nonfiction, you're supposed to use the trademark symbol whenever using a brand name, but this really doesn't hold in fiction. A trademark symbol just doesn't go over in narrative.
It would be a strange character who lived in a world that has no brand name products and no famous people and no famous songs.
A little bit of brand name use goes a very long way. It gets old fast. But there's nothing at all wrong with having a character drive a '65 Ford Mustang (Which is what Mike Hammer drove), or having a character drink a Bud Light, or saying you a character hears Frank Sinatra singing "I Did it My Way" on the radio. Thugh I'd probably write taht when the character stepped into the bar, Sinatra was on the jukebox sining about doing it his way.
It's really the same as using real locations. A character walks through Central Park, or goes to the top of The Empire State Building, or picks up a copy of The New York Times and scans the headlines.
Too many brand names reads poorly, but using some simply adds veristimilitude to a story. But it is like using cayenne pepper. . .too much is a bad thing.
Most often, a car is referred to as a car, or a character says, "I drank a beer," etc. But when needed, brand names and real people can make the difference.
You usually don't have to worry about this unless you write contemporary fiction set in the real world, and sometimes it's fun to make up your own brand names, your own music groups, complete with your own song titles and lyrics, but sometimes the real deal makes the difference in contemporary fiction set in the real world.