Sure you can. There is no predictability and no fundamental laws in a purpose-built universe run by an omnipotent creator because ultimately the creator can do anything they please.

Not to get all reddit atheist here, but as far as we can tell, the universe is predictable and explainable by fundamental mathematical laws. (We don't see, for example, unexplainable violations of conservation as Michael Landon pops in and out of existence.)

This could mean there is no god or they don't interfere or whatever, but in any case it's pretty good evidence that we can reason about how the universe works.

That's about as good as you can know anything. Beyond that is the "Are you a brain in a jar" kinds of philosophical arguments that are fun when you're 21 and get old after.