God exists or not?

Disclaimer: This is an excerpt from a website article http://www.theflabbergastedindian.com/2017/05/the-almighty-god-debunked.html

It is said that humans cannot even lift a leaf without the almighty God’s consent. Also, the law of Karma suggests that whatever good or bad we do, equal or more good or bad will happen to us.

But hey, if I can’t do anything without the consent of God, how can I commit a bad deed? And if I did commit a bad deed (with God’s consent) and then because of my Karma, if such bad happens to me, is God to be blamed? Also, if God is omniscient, it would mean he knows the past, the present and the future. If he knows the future, it means the future is fixed. And if the future is fixed, God cannot change it. But isn’t he omnipotent, the all powerful? If he is omnipotent, he should be able to change the future but that would make him “not omniscient”. You see the problem?