Is it permissible to acquire a copy of the Injeel to learn about God’s words to our Master Jesus, and is the Injeel that exists today authentic, especially after I heard that the original Injeel drowned in the Euphrates?

It is not permissible to possess books that predate the Quran, such as the Injil (Gospel) and the Tawrat (Torah), because the Quran has clarified everything beneficial within them and suffices for them. All good found in those books is present in the Quran. The Injil currently in existence is corrupted, as evidenced by the presence of four conflicting Gospels. However, there is no objection for a knowledgeable student of Islamic sciences to study them in order to refute falsehood and establish proof.