subscription, you can download entire albums for offline listening. Apple Music / iTunes
Idols from popular groups (like BTS or EXO) often record tracks to draw their existing fanbases to the show.
: Many independent artists and official OST creators upload tracks here. Some tracks may have a direct "Download" button provided by the artist.
Open a new tab. Go to Amazon Music. Search for "Crash Landing on You OST." Click "Buy." And let the healing begin.