According to Songfacts.com this was one of the first Pop songs to start with the chorus rather than a verse. That was producer George Martin's idea.
When pressed by American journalists in 1966 to reveal the song's "true" meaning, McCartney denied that "Can't Buy Me Love" was about prostitution, stating that, although it was open to interpretation, that suggestion was going too far, saying: "The idea behind it…
Can't buy me love, love
Can't buy me love
I'll buy you a diamond ring my friend