As an artist, first you must ask yourself whether you want to sell copies of your song or not/give it away for free. If you’re song will be used for non-commercial use, you do not need a license.
If you intend to upload to Spotify, Apple Music, SoundCloud etc. and monetise your streams (make money from your streams) then you’ll need to purchase a lease.
Depending on how big you are trying to go with your song, you then need to choose a leasing option that best suits your project.