So I was listening to the song "我的新衣” by Vava, and at a point the rapper Ty sings. And for some reason in this verse走到街上就像一千台进口奔驰 instead of 街 I listen he raps kāi. Can someone please tell me what he raps? Is it maybe some local accent and that's why I'm not hearing him pronouncing 街（jiē）properly? Thanks!
The pronunciation is most likely from a topolectical influence. If you check Wiktionary's entry on「街」, for example:
EDIT: as @user3306356 has noted, the rapper is speaking/rapping/singing in a topolect of Chengdu.