Where did the laws of physics come from? We, human of course.
Let's not forget that science is a discipline based on evidences - observations of nature which are repeatable, demonstrable and time-independent. Scientific theories are formulated to "explain" observations. Here "theory x explains observation a" is a short hand of saying that observation a also supports theory x. However, being a generalisation of a set of observations, theory may include other possible observations which were not used in formulating the theory. Experiments will be devised to test whether all these other possible observations are true or not. That's how our understanding of the universe improves. By knowing more about the physical reality, we are able to exploit the physical reality better such as by inventing tools, machineries, gadgets, vaccines, medicine, ....
Human's total body of knowledge increases because of the accumulation of evidences. Obviously without theories, the size of body of evidence will be overwhelming to be useful. Theories help by reducing large sets of evidences into concepts for remembering as well as for application.
Ideally, the collective theories from all fields will represent a model for the physical reality we inhibit. We are still far from understanding everything about our universe. May be it will be an everlasting business. But that's for another post.
On the literal level, the laws of physics come from human invention. We invent ways of grouping evidences and then provide a generalisation to the group in the form of a theory. It is one way to understand the reality we inhibit. There may be other ways. However, the methodology - the scientific method - proves to be useful for the last few centuries and we are adhering to this method when there is no other better methodology.
The questioner is actually asking for a deeper level. The question is only the proxy for "where did the regularities as described in physical laws came from"? Once rephrased in this way, we see a problem. Our physically reality is NOT really that regular? Look at the trees, no two are exactly the same. Look at the leaves, it will be very difficult to find two which are exactly the same. Look at any natural landscape, it will be unique. Moving out to the galaxies, every galaxy is different from another. You and me, even twins are different.
If there were a creator of the universe, why everything are different?
We human are good at finding patterns, repeatable patterns. We ignored the "minor" differences in formulating scientific theory because the purpose of formulating a theory is for us to use as a short hand for a set of observations.
Question: why supernatural is automatically off-limits as an explanation of the natural world?
Answer: [highlight to show] Supernatural observations are not repeatable and demonstrable. It may be an once off observation or a delusion. It has no value in the understanding the "regularity" of our physical reality and it offers no value as an explanation to the observation.