AnswerYes. God is a construct of man.
Due to many factors.
Humans have always believed that what is "real" is what you can see, taste, touch and hear, but there is no way to really do any the previous when it is referring to "God".
For some, gods are merely constructed in man's mind: therefore without raising too many questions about the "existence" you only need to look at the facts.
Some believe that god created well everything and is everywhere: hence this brings comfort to people knowing that a "supreme being" is watching their every move.
Another way to look at it is to see that humans are the only species on earth who feel the need to pay worship to "god", attend church, and pray. The "commandments" laid down by the church are there for only humans to follow. No other species is bound to these rules.
AnswerYes, almost certainly mankind has made up the idea of gods. The gods are always so very like humans, and many gods even take on human form: the Roman and Greek gods looked human, for example, and Christians believe that their god became a man literally.
But there is no evidence to suggest that any of the gods are real, and the myths and legends told about gods are your standard legend material, really.
Most religions have been influenced by previous religions. Much of the Christian religion, for example, came from the cult Mithras, including eating bread and drinking wine to represent the body of the god-man who was the saviour.
When you examine religions closely, they look less and less miraculous and more and more like things which people just made up.
Too many logical fallacies, bias, and debunked information in these answers... is this tongue in cheek humor?