What is it that God/Allah really want from us?

Does God want human beings to have different religions?
Before Jesus was born there was already the Old Testament, Christians and God. People then who prefessed to the teachings already believed in God. God then brings His son to the Earth so that more people will believe in Him and thus will be saved. However this split the people into at least 2 groups, those who believe in Him but not Jesus and those who believe in Him and Jesus.

Seven hundred Earth years later, God sent another Prophet, Muhammad, to Earth to tell human beings to believe in Him (Allah/God). This split the people further into more groups, the first group who believe in Him but not Jesus or Muhammad, the second group who believe in Him and Jesus but not Muhammad, and now the third group who believes in Him and Muhammad.

These three groups, (let's leave out those who don't believe in Him here) if they follow the teachings to the dot are to love thy neighbours, love all beings, be compassionate, knows that He is the greatest and ultimately they will be seeing him, then why are there so much misunderstandings? Did God send His son and the prophet to earth so that we can cling on to who and what we want to believe and so that we can be in conflict with one another?

Think about it. Did God send His son down so that those who believe in Jesus can call themselves Christians? Or did He send prophet Muhammad so that there will be another group of people who can call themselves Muslims? Or did He simply want human beings to believe in Him so that ALL can live a virtuous and happy life and in harmony with everyone?

Are we doing what He wants us to do or are we deviating from His real message? Is there more peace and harmony or more deaths and conflicts and anger with those who believe in Him?