Short answers, pulled from the story.
Paul McCartney wrote the melody for The Long and Winding Road in 1968 while sitting at a piano inside High Park Farm near Campbeltown in Scotland. He composed the song looking out toward the hills and lochs surrounding that remote Highlands location.
Paul McCartney performed lead vocals and piano throughout the sessions held on the 26th of January and the 31st of January 1969. John Lennon played bass guitar, George Harrison added electric guitar with a Leslie speaker effect, Ringo Starr performed drums, and Billy Preston played electric piano.
Phil Spector added orchestral overdubs including eight violins, four violas, four cellos, three trumpets, and three trombones during a session on the 1st of April 1970 at EMI Studios. He also removed one of McCartney's vocal tracks and deleted Harrison's guitar parts and Preston's piano from the final mix.
The single reached number one on the Billboard Hot 100 chart on the 13th of June 1970 after being released in the United States. It held the top position for a second week following its initial release date.
John Mendelsohn condemned the work as oppressive mush while Rolling Stones reviewers criticized hideously cloying strings and a ridiculous choir. Ian MacDonald called it one of the most beautiful things McCartney ever wrote and Brian Wilson described it as his all time favorite Beatles track.
Paul McCartney performed fragments of the song during One Hand Clapping before including it in Wings' 1975, 76 world tour set lists. A live version appeared on the 1976 album Wings over America and he re-recorded the track for his 1984 film Give My Regards to Broad Street with George Martin producing.