Jews dont believe in the devil. From what I know about Judaism, they believe that Satan is simply an angel that God uses to accuse people-they dont really believe that he's a fallen angel or devil figure. Jews only believe in the Old Testament (Torah.)
But where exactly does the Old Testament say that Satan is a fallen angel or the devil? The book of Revelation refers to him as the devil and the serpent in the Garden of Eden, but that's in the New Testament, not the Old. Even the Book of Job never explicitly states that he's a fallen angel. Some people would argue that the Book of Ezekiel refers to Lucifer, but you could only put the dots together to realize that that verse is talking about the devil, if you know what the New Testament says about him.
But where exactly does the Old Testament say that Satan is a fallen angel or the devil? The book of Revelation refers to him as the devil and the serpent in the Garden of Eden, but that's in the New Testament, not the Old. Even the Book of Job never explicitly states that he's a fallen angel. Some people would argue that the Book of Ezekiel refers to Lucifer, but you could only put the dots together to realize that that verse is talking about the devil, if you know what the New Testament says about him.