frummy, when you say “proof” you can refer to different things. You see, there is mathematical proof, scientific proof, proof based on the preponderance of the evidence, proof beyond a reasonable doubt, circumstantial proof, historical proof, etc.
so what kind of proof are YOU looking for?
Furthermore, when you say “torah min hashamayim” what do you mean? that too can mean different things to different people. for some, it means that gd actually wrote or dictated the tanach, for others, gd inspired others to write it, for others still, gd sanctioning its writing after the fact. what about torah shebe’al peh? that is also min hashamayim but means different things to different people.
in sum, your question is too vague to be answerable.