Debates for and against the existence of God have been going on for thousands of years, and no one seems to stand out as a winner. This is not very much of a religious question but rather a philosophical one, just to clarify, as different religions do have different Gods of different identities and different functions. The controversial idea of God arises as there are ultimate questions which we human beings are not capable of answering with convincing evidence. Examples could be where did we, or even the universe come from? What is the meaning of life as we are all going to die anyway?
Plenty of arguments proving that God does exist have been raised. Some classical examples would be 1) the Cosmological Argument argues that everything has a cause, the causal chain does not go back forever, so God must have been the first cause; 2) the Ontological Argument states that God is the greatest thing ever by definition, if it didn’t exist, we could think of something greater, but our definition of God tells us that it is impossible to think of anything greater, so God must exist; 3) the Design Argument brings up the idea that if you saw a watch in a jungle, you must have believed that someone must have lost it here instead of it was there since the beginning of beings because of the complexity of the design, so as everything works well in our universe and in our body, someone must have designed the universe and us, too, and that one must God. As we think about these arguments, they are not flawless, and so debates against them are also brought up. Counter-arguments could be, but not limited to 1) what caused the first cause in the Cosmological Argument? 2) a problem with the Ontological Argument would be the definition of something does not prove its existence; 3) who created God in the case of the Design Theory?
The debate has not yet been settled and is likely to go on for a while. Even though people hold different opinions towards the problem, all religious beliefs should be respected and valued.