There are several platforms where you can earn money by composing songs, such as:
1. Songtradr: Songtradr is a music licensing platform that allows musicians to license their music for use in films, TV shows, commercials, and more. Musicians can earn money every time their music is licensed.
2. SoundBetter: SoundBetter is a platform that connects musicians with music producers, engineers, and other music professionals. Musicians can offer their songwriting services on SoundBetter and earn money by composing songs for other artists.
3. Fiverr: Fiverr is a freelance marketplace where musicians can offer their songwriting services to clients around the world. Musicians can create gigs offering to compose songs for clients and earn money for their work.
4. Patreon: Patreon is a platform that allows musicians to earn money from their fans by offering exclusive content, such as new songs, behind-the-scenes videos, and more. Musicians can set up a Patreon account and offer exclusive rewards to their patrons in exchange for their support.
These are just a few examples of platforms where you can earn money by composing songs. It's important to do your research and find the platform that best fits your needs and goals as a songwriter.