Well, the basics of stellar simulation are grounded in the stellar structure equations, which any undergraduate stellar astrophysics course would cover. And even with MATLAB there are definitely things you can do to model stars, but only stars that are in hydrostatic equilibrium. When it comes to modeling the time evolution of stars, especially stellar collapse, you need a full code to do that, and it's non-trivial to make. If you want to see stellar structure codes in action, check out MESA (which is written in FORTRAN):
But a one-dimensional code can't possibly model supernovae, which we now know are fully three-dimensional events. For that you would need a more complex code and there are definitely some out there that can do it to some extent (e.g. the FLASH code) but you'll want to be familiar with the simple 1D codes first.
MESA is lots of fun to work with just for seeing normal stellar evolution in action, and I have been able to get some stellar explosions (e.g. novae, x-ray bursts) to be modeled through it; but collapse and supernova events are too much for it. Nevertheless, it's a very advanced modern code, and can do (or reasonably simulate) nearly everything else.
Well, my intention is to ultimately simulate a model GRB. Perhaps that's too far fetched. Nevertheless, one has to start with the basics first. thanks again.