KK had got his break as a playback singer with AR Rahman’s hit songs, Kalluri Saaley and Hello Doctor and his first Bollywood song was Chod Aaye Hum Who Galiyan from the film Maachis. However, it was the superhit track, Tadap Tadap Ke Is Dil Se from the film, Hum Dil De Chuke Sanam , that had made KK a huge sensation.

https://www.bollywoodshaadis.com/articles/rare-and-unknown-facts-about-singer-kk-32810