From Google:

"Your Song" is an iconic ballad written by Bernie Taupin and Elton John, serving as the breakthrough hit of their legendary musical partnership.

Origin and Creation

• Lyrics Written: Bernie Taupin drafted the lyrics in about 10 minutes on October 27, 1969, while sitting over breakfast at Elton John's mother's house.
• Music Composed: Elton John wrote the melody in approximately 20 minutes right after Taupin handed him the words.
• Inspiration: Taupin was around 17 years old when he originally conceived the naive, innocent sentiments of the track. He deliberately avoided gendered pronouns so the words could feel universal.