Showing a movie or performing a musical work in a public setting (e.g., a club or organization) usually requires purchasing a public performance license. Just as you cannot rent a movie from a local video store and then screen it in a public space, you cannot show movies or perform musical works in a public setting without purchasing a public performance license, even if you're not charging admission.
An exception to this rule is when you are showing the film or playing the music in a face-to-face course.
When purchasing public performance rights, you will have to provide the distributor with: