The scientific method can never really "falsify" anything
Good morning Hoppyland.
We are almost certainly talking at cross-purposes here. Popper's principle was about scientific method, not about trying to use science to disprove the existence of (for example) God.
If we formulate a hypothesis, he argues, we must be able to say by what means we could show that hypothesis to be false. If we can do so, then we can do science, if not then the subject is not amenable to science.
Let's suppose our observation leads us to propose that the Earth is, while a bit bumpy, essentially flat. We can devise methods by which we might show that to be wrong, eg., going to an observation point well away from the surface and seeing that we have in fact a rotating sphere.
Similarly, the phenomenon of ships' masts sinking below the horizon might lead us to wonder if the Earth's surface were not curved. We could check whether our theory was false in the same way. Our method shows us that the Earth's surface is indeed curved, but it might have shown us otherwise. We had devised a method which might have shown our hypothesis to be false (even though it isn't) and so according to Popper, the question is amenable to science.
My point was that we haven't yet found a way of demonstrating that "God exists" is false and so the issue is not amenable to science. In fact many would argue that the declaration is, itself, meaningless. Conversely, if we could come up with a reliable method of showing that God does not exist, other than eschatological verification, then we can start doing science.
No doubt Popper doesn't have the last word on the matter. Nevertheless, it's certainly worth looking him up. It works for me.
Perhaps we should move our discussion to a philosophy forum as we've moved a long way away from home brewing and from the original poll. Just googled this to see if there was anything interesting out there:
https://thephilosophyforum.com/search?Search=science