If you prefer not to buy the file individually, you can download it for offline listening through subscription services:
: Third-party "MP3 converter" sites often contain intrusive ads or malware. River Flows In You MP3 Download
For a permanent MP3 file that you can keep and play offline on any device: If you prefer not to buy the file
: If you use macOS or Windows, you can buy the song directly via the iTunes Store to download it as a high-bitrate AAC file (which can be easily converted to MP3 if needed). Streaming for Offline Use River Flows In You MP3 Download
: Buying or streaming via official channels ensures South Korean-British composer Yiruma receives royalties for his work.