Is programming an emulation of the real world?
This is a third true, a third false, and a third unknown.
Why you might think its true
As you have stated, it does intuitively makes sense that any kind of &quot;computation&quot; or &quot;effect&quot; in the real world has an equivalent computation in the computer. After all - the world we know is compromised of atoms and such, and it makes sense we can store such data in bits. If im not mistaken, the Church-Turing hypothesis that was based on this intuition hypothesizes that anything that can be done in the real world can be done in a computer
Why we might think its false
Think about our world - it has a lot of people, which independently and simultaneously do things. This kind of behaviour is not really natural for a computer - a computer can only process one thing (or at most a handful of things, if it has a few cores) at once. This leads us to think it might be impossible to think of the world as a giant computer.
Why we still don't know, and will probably never know
Physics is a branch of science that always develops. There is always more to uncover about our universe and its underlying mechanisms. Therefore, there will always be a way to create a newer and mpre sophisticated computer that can do more things. For example, the recent developments for quantum computers might change things up: In a quantum computer there are things that can be computed faster than in a normal computer. In fact, a quantum computer is capable of doing something similar to parallel computing (a common misconception is that it does compute in a parallel way, but actually it does something else that creates this effect).
This means that both statements for why it could be true and why it could be correct! It might be true that normal computers can't emulate all of the stuff that can be done in the real world, but don't know whether it will still hold for a newer computer based off of a brand new idea in physics that would be developed in a few hundred years from now.
Still, this is only my own opinion. If you want more (and probably better) answers, you might want to consider asking this to philosophers.