Sure -- it is possible that the universe as we perceive it is actually something entirely other than what it seems to be, so that gravity really doesn't work the way it seems to, the laws of thermodynamics are all illusion, and the stars really are holes in a vast black velvet dome that covers our flat earth, But the likelihood that this is the case is not very, well, likely.

We can say "there are no facts", and if we want to we can proceed on that assumption and, by golly, the world as we know it will continue to function pretty much as it always has -- altho we may end up immolating ourselves as we dismiss the "fact" that fire burns, or suffocating when we seal ourselves in an airtight room, because we do not accept this "fact" that we need oxygen to breath.

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Again, we come back to the different way scientists and civilians use the word "theory". In science class in school -- a place where, it should be noted, all manner of drivel is presented as fact -- we are taught that there are three stages to knowledge, hypothesis, theory, law. Something is not "promoted" to a Law until it has been "proven", so a theory is, by definition, something which has not been proven.

Except that's not how real scientists use the term. In their world, a theory is something that has not been proven by observation. So, as with the earth moving around the sun, or atoms, or evolution, every scrap of evidence may point in that direction, but there is no practical way to do experiments which will present repeatable results every time. (We could, indeed, set up an experiment which would test evolution, for instance, but it would take hundreds of thousands of years, even millions of years*, for this experiement to play itself out, and even then it would have to be done at least a second time before the results could be considered valid.}