In Hinduism the concept of prophet is called avatar and it has the same meaning in its own language also. The word avatar comes from utara also and it is the same thing as a messenger in our language today. Promised Messiah(As) explained it to the Hindus in their own way, to Christians in their own way and to Muslims in the way they would understand to make it clear. Some have the misconception that Krishna(as) claimed to be God but this is totally false. He did not claim to be God and nor did Jesus(as) rather their messages were corrupted by the people who exaggerated their claims to a point where they made both of these prophets gods.
The Holy Qur’an is the greatest book and is the only book which states that you should accept all messengers. All people were given a prophet. Some claim that the Hindus did not have a prophet nor did India but this is totally false. There is a hadith which states:
“There was a prophet of God in India who is dark in color and his name was Kahan [Krishna]” (History of Hamadan Dailmi Chapter Al-Kaaf).
The teachings of Krishna also had tauheed and he was a true prophet but after he died his people began to worship him just as what happened to Jesus(as). He was a prophet but later worshiped. Its also clear that there are prophecies of Muhammad(saw) in the Hindu Scriptures as the Kalki Autar and Islamic scholars believe in these prophecies, for example Zakir Naik. Zakir Naik has clearly stated that Muhammad(saw) is the Kalki Autar and today he is followed by millions as a great scholar.
Here is one verse from the Bhagavad-Gita showing that Krishna(as) did not claim to be a prophet:
“Krishna. I Brahma am! The One Eternal God” (Bhagavad-Gita 16:9)