Spotify provides artists with a straightforward method to submit music for playlist consideration.
To be considered, your release date must be at least three weeks in the future.
Check out Spotify's guidelines on pitching music here:
https://artists.spotify.com/blog/share-new-music-for-playlist-consideration
Here's an article that explains how Spotify's curators make decisions: https://artists.spotify.com/blog/behind-the-playlists-r-and-b
Best of luck!