Why are there so many religions and gods all over the world? Come to think of it, when the idea spread, why did people develop different gods and beliefs rather than follow the same one?

If the idea of a god did develop independently, without any interference from different locations, how could the same patterns and concepts of a god, religion, heaven, and hell emerge?

Is the thought process of humankind that similar, or is this indication that God or a supernatural being exists?

This question is probably more aligned with history or anthropology than philosophy.

People began believing in gods thousands of years ago, long before modern transportation and communication. How was a person living in Africa supposed to know about the existence of a distant tribe that would one day evolve into the Mongols, let alone what god(s) the tribe believed in?

Even groups of people that live close together may be nevertheless separated by natural barriers (e.g rivers, mountains) and language/cultural barriers.

“If the idea of God did develop independently, without any interference from different locations, how could the same pattern and concepts of God and religion and heaven and hell emerge?”

Is there really a well defined pattern of belief in heaven and hell? Belief in an afterlife may be pretty common, and that afterlife can be perceived as good, bad, or somewhere in between. But I think Heaven and Hell is a concept more closely aligned with Christianity, Islam, and Judaism than Eastern religion, and I suspect Native American and Australian religions were also fairly divergent on that score.

This is an opinion-based question. Just in case people think otherwise, I will give one example of an answer.

The Catechism of the Catholic Church (which summarises the beliefs of the Catholic Church, emerging from centuries of theological scrutiny [notice theology tag in the question]), states the following:

I. The Desire for God

27 The desire for God is written in the human heart, because man is created by God and for God; and God never ceases to draw man to himself. Only in God will he find the truth and happiness he never stops searching for:

The dignity of man rests above all on the fact that he is called to communion with God. This invitation to converse with God is addressed to man as soon as he comes into being. For if man exists it is because God has created him through love, and through love continues to hold him in existence. He cannot live fully according to truth unless he freely acknowledges that love and entrusts himself to his creator.

28 In many ways, throughout history down to the present day, men have given expression to their quest for God in their religious beliefs and behaviour: in their prayers, sacrifices, rituals, meditations, and so forth. These forms of religious expression, despite the ambiguities they often bring with them, are so universal that one may well call man a religious being:

From one ancestor (God) made all nations to inhabit the whole earth, and he allotted the times of their existence and the boundaries of the places where they would live, so that they would search for God and perhaps grope for him and find him - though indeed he is not far from each one of us. For "in him we live and move and have our being."

Importantly, this is from the beginning of human kind. As humans have been distributed all over the world, so different religions and belief spread throughout the world. The key is that those different gods represent idiosyncratic features of the satisfaction of a common desire, i.e. to seek [the true] God.

Yet, according to Judeo-Christian religions (Judaism, Christianity, and some might even say Islam), God did not remain invisible all the time. He decided to revealed Himself to some individuals and groups. The Catechism states:

Through an utterly free decision, God has revealed himself and given himself to man.

This revelation was progressive in the sense that He revealed only parts of Himself at a time. For instance, God chose Abraham in order to build a "chosen people", which later on gave rise to Judaism. According to Christianity, God's self-revelation was fulfilled (i.e. finished) in Jesus Christ, giving rise to Christianity.

The above is an example of why there are different religions and "different gods", according to one Christian tradition.

tl;dr

God(s) are not so much the common factor to the world's religions (and philosophies) as spirituality.

Some examples to illustrate

Hinduism

The pontiff Sankara acharya said :

It is not necessary (for a Hindu) to believe in many some or one god but it is necessary to believe in the afterlife (ie spirit) and in the karmic law

Christianity

In different ways and forms the gospels repeatedly assert

The sin (blasphemy) against the Father can be forgiven and against the Son but never against the holy spirit

Socrates

In one of the rare admissions to his specialness attributed it to his daemon ie spirit.

Moonhawk

The American Indian moonhawk said:

The white man's god is a noun whereas our (native American) god is a verb.

Wittgenstein

Wittgenstein was writing the Tractatus in the face of death during WWI. he said:

Perhaps the nearness of death will bring me the light of life. May God enlighten me. Through God I will become a man. God be with me. Amen.

It's ironical how spirit-ual in source is this favorite of the logical positivists!

In short God /gods are are not the common factor to the world's religions; the call of the spirit – spirit-uality – is.

Douglas Harding

A very succinct non-sectarian rendering of how ridiculous it is to think of oneself as a thing in a world of things rather than the ground of consciousness on which all things have their being is Douglas Harding's On having no head. IOW Harding makes a powerful case that we are fundamentally spiritual beings not material bodies.

• There is a school of thought sometimes called the Perennial Philosophy, which holds that all religions and all philosophies are reflections of a singer greater truth, which cannot be fully contained by any of them. An obvious ancestor of this theory is Plotinus' Neoplatonism (and, if you accept Plotinus' arguments, the work of Plato himself). The best-known recent exponent in the English-speaking world was probably Aldous Huxley. According to that point of view, the commonalities in religion are (largely) significant, whereas the differences are accidents of culture and history.




• Anthropologically and sociologically speaking, there are some major structures that appear again and again in religions all across the world. It may be difficult to determine whether these are innate, or culturally transmitted, but what is notable is that they often cross the boundaries of any given religion. These include polytheistic, ancestor-venerating, Goddess worshipping, monotheistic, non-theistic, mystical and messianic. For instance, Buddhism is an abstract, non-theistic religion, but Amida Buddhism is messianic, and the concept of the bodhisattvas resembles polytheism. Similarly, Christianity is a messianic, monotheistic religion, but the veneration of the Virgin Mary resembles goddess worship, and the veneration of the saints resembles polytheism and/or ancestor-veneration. In the same way, there are mystical forms of Buddhism, Christianity, Islam (Sufism), Hinduism and Judaism (Kabbalah).



• 
  Some religions are clearly related, influenced by, or descended from each other. Judaism, Christianity, Islam and Rastafarianism all trace back to a single Biblical patriarch, Abraham, and members of Latter Day Saints, Seventh Day Adventist and Santeria religious communities all consider themselves to be followers of the Christian religion. Buddhism grew out of Hinduism, and later developed into Zen. The Roman pantheon was transparently influenced by the Greek one.

Man invented different Gods / Religions in order to control different groups, because each group/nation is different. But the main goal is to control people by fear.