The nature of knowledge is seen differently for theists and atheists. Theists are more consistent in that they think the bible, morality, logic, mathematics and the laws of physics all exist independently of humans. In other words they think concepts are real. The test for reality is whether something can have an effect independently of its concept so theists are wrong on all these subjects. Surprisingly enough atheists are often wrong too.
Atheists have worked out that the bible was written by people and that idea, more or less, defines them as atheist and their attitude to knowledge. Slightly more difficult is that morality is a socially agreed concept based partly on evolved emotion and partly on cultural learning. The technical subjects are the most difficult. Atheists sometimes copy the theist idea that people discover logic and mathematics. It is not true, logic and mathematics are like games of chess where you make a set of assumptions and follow the consequences. It is possible to make different rules, maybe you can add another piece to the board or change the way a piece moves. No system of logic or mathematics will cover all situations. There is at the moment on YouTube a video by someone complaining that modern mathematics is inconsistent with its roots and not properly derived. What does he expect? Mathematics has to be defined to do a particular job. It is impossible to have a single system of mathematics or logic. Mathematics and logic are just human tools to be used in particular situations and not even all situations. Does anyone use logic to decide who to love? No, logic does not apply to that situation. The most difficult concept is probably the laws of physics. People in general often assume that the laws of physics are themselves reality. Actually people make them up. When a scientist makes up a law, the universe doesn't care. The universe might do something different and the law is wrong. On the other hand the universe might agree with the law. In that case it is a useable description. Is the description actually correct? No, it is just a description that can be used in a particular way. The description is like a painting. You look at a painting of a country scene and there is a village in the background. Maybe you want to know more about the village, so you take out a magnifying glass to look closer. It is blobs of paint. You can't learn more about the village. A philosopher like Berkeley looks at the painting and describes the whole of the countryside based on what he sees. He is wrong because the painting doesn't describe everything in the way he thinks. So does a law of physics describe anything real? Does the universe pass the test of reality that it has an effect independent of the concept? The universe is real, but the effect might not be what you expect. This is Niels Bohr "It is wrong to think that the task of physics is to find out how nature is. Physics concerns only what we can say about nature."