Ghost Riders in the Sky, sung by my Dad with his guitar to me & my brother. I was 4 years old.
The Cruel Sea by the Dakotas was the first song I learned on lead guitar with a group in 1963, aged 15.
Don't Worry Baby by the Beach Boys. That was my type of music, and I follow vocal harmony still.
Yellow River by Christie was the first song I sang in a professional band in 1970 at age 22.