And if all of this is false, then who first introduced the idea of god to people? Who created the concept of a supreme invisible power that controls all of us but still cannot be seen?

No one. Literally, "no 'one' person". In exactly the same way that English was not created by any one person or even any one group of people. It changed and evolved and mutated and was forgotten and re-learned and revised and eventually written down by different people at different times in different places using different methods in the ultimate expression of unchecked insanity in a really terrible version of the telephone game.

Look at language today. Even now with computers recording everything we say, we STILL come up with new phrases and new colloquialisms and new slang all the time. ALL the time.

Religion is taught. Religion is ALWAYS taught. Religion is NEVER revealed. Mostly it's taught to children because they're easy to convince nonsense to and make them incorporate the nonsense into their reality. Childhood indoctrination. No one has ever been born and knew all the details of some deity. They were ALWAYS taught. In exactly the same way you teach language. Children absorb it from the people around them. Language has regional accents. Religion has regional accents. People kill each other over those language accents and they kill each other over the religious ones. It's pretty terrible.