If God is only a belief, God is not real, so that means God does not exist.
If God exists, God is real.
Now do you understand the difference?
Not really.... Plate tectonics is a belief, so is flat Earth, hollow Earth, elephants and unicorns, Donald Trump and Batman -- all various types of beliefs.
Who sets the standards for evidence and what it should be like? Who determines what is flawed evidence? Why does evidence have to be tangible?
I'm assuming you have the the self-validating evidence of religious ecstasy or the mystical experience in mind.
I can relate to that. Mysticism informs my own metaphysical outlook, as well, but it is only evidence if it can be examined and evaluated by others; if it can be perceived by others and violates no known physical laws or rules of logic.
Evidence must be examinable, and, preferably, testable. Ergo: it must be
tangible.
Who sets the standards? Logicians, mathematicians, scientists, epistemologists &al.
Evidence is determined to be flawed if it doesn't stand up to scrutiny; if testing doesn't support it or if it's not reproducible.
Geocentrism, phlogiston and phrenology were widespread beliefs at one time, but they were never facts. They failed the evidence tests.
On the other hand, academics once ridiculed the idea that rocks could fall from a clear, blue sky, but, counter-intuitive as that seems, it passed the evidence test and is now generally accepted.
Evidence is by definition the available body of facts or information indicating whether a belief is true or valid. If it does not indicate whether a belief is true or valid to you, it is not evidence to you, but it it indicates that a belief is true or valid to me it is evidence to me.
Truth and falsehood are universals. There is no personal truth; no "true and valid
for you."
A thing is either existentially true or it isn't. An argument from fallacy, affirming a disjunct or an illicit major are fallacies for everyone, everywhere. "All dogs have six legs" is unsupported and unevidenced for everyone, no matter how fervently you believe it.