She is a famous singer so I think I've heard one of her songs before.
She is popular so I'm pretty sure I've listened to one of her songs before.
どちらも「彼女雨は有名だから、彼女の曲のどれかは聞いたことがあると思います。」という意味です。
「聞いたことがある」は
I've heard ...
I've listened to ...
と言います。
one of her songs で「彼女の曲の1つ・彼女の曲のどれか」
1) She is a famous singer so I think I've heard one of her songs before.
famous singer で「有名な歌手」
2) She is popular so I'm pretty sure I've listened to one of her songs before.
popular で「人気のある」
ご参考になれば幸いです!