Billie Eilish Pirate Baird O'Connell (/ˈaɪlɪʃ/ EYE-lish; born December 18, 2001) is an American singer and songwriter. She first gained public attention in 2015 with her debut single "Ocean Eyes", written and produced by her brother Finneas O'Connell, with whom she collaborates on music and live shows. In 2017, she released her debut extended play (EP), titled Don't Smile at Me. Commercially successful, it reached the top 15 of record charts in numerous countries, including the US, UK, Canada, and Australia.

Eilish's first studio album, When We All Fall Asleep, Where Do We Go? (2019), debuted atop the US Billboard 200 and UK Albums Chart. It was one of the best-selling albums of the year, buoyed by the success of its fifth single "Bad Guy", Eilish's first number-one on the US Billboard Hot 100. This made her the first artist born in the 21st century to release a chart-topping single. The following year, Eilish performed the theme song "No Time to Die" for the James Bond film of the same name, which topped the UK Singles Chart and won the Academy Award for Best Original Song in 2022. Her subsequent singles "Everything I Wanted", "My Future", "Therefore I Am", and "Your Power" peaked in the top 10 in the US and UK. Her second studio album, Happier Than Ever (2021), topped charts in 25 countries.
Given this paragraph about Billie Eilish, tell me who produced her debut single, also tell me what is her chart-topping single?
Her brother Finneas O'Connell produced her debut single "Ocean Eyes", and her chart topping single is "Bad Guy"