“I Will” is a song recorded the Beatles, from their 1968 double album The Beatles (also known as “the White Album”). It was written by Paul McCartney.
I’ve always particularly liked this song. Paul must agree, because according to McCartney: “It’s still one of my favorite melodies that I’ve written. You just occasionally get lucky with a melody and it becomes rather complete and I think this is one of them; quite a complete tune.”