Early Morning Rain was a hit for Peter, Paul & Mary in 1965, which put Gordon Lightfoot on the map at the beginning of his songwriting career. It had been released before but PPM had a much bigger audience than Canadian artists Ian & Sylvia, at least in the US. Typical of their arrangements, they expanded the chord progression and added great harmony and answering vocals.
This song is best done with what I call 'generic' fingerpicking, meaning there is no one correct way to do it, it can be changed and improvised every time. This lesson is really a comprehensive introduction to this style of fingerpicking, showing some core patterns and variations, and then examples of embellishments and fills. Once the student understands and can execute these techniques, the door is open to thousands of songs that can be played in this style.