Well, first one has to understand what "God" is. There are groups that believe in multiple Gods. There are other groups that believe God is a part of His creation, that God is limited to a certain effect, or that God can die altogether! All of these other beliefs of what people believe to be "God", goes against the very idea of what God is. Islam is about as clear as can be on the definition of God and there is no complicated formula to try and understand Allah. All the prophets worshiped Allah. Whether or not a Jew, Christian, or Atheist believes it, makes no difference to the fact.
You have perfectly demonstrated the problem .
People define what a god is .
People from cultures all over the globe , for 10,000 years ( at least) have created deities in an attempt to explain the universe and our place in it.
Gods are a concept, an idea , they are created and developed by people,
They are based on the things we do kit know our understand.
Don’t know how the universe came to be ... create a god to explain it
Don’t know how life began ... create a god to explain it
Afraid of death , create a god that supplies an afterlife.
Gods are a primitive attempt to explain the universe ... it would be much more intellectually honest to just say ... I don’t know .
Then you can say what you believe ,
You have your religious beliefs , just like Hindus have theirs , jews have theirs, Christians have theirs, the Norse had theirs.
Do you agree it’s possible for large numbers of people to believe things that have no basis in reality , thus is especially true in relation to gods and religions ?