I have recently started with my highschool course on semiconductors and after a general introduction as to what they are, I have graduated to the p-n junction. Almost all resources that teach the textbook course explain joining a p-type and n-type semiconductor in same way; the electrons and holes of n- and p-type semiconductors respectively diffuse due to their concentration gradient to the corresponding opposite side thus setting up a "diffusion" current. This creates a sort of charge separation$^1$ at the junction (why? Why don't the electrons that diffused from n to p combine with the holes there and kinda neutralise?) which keeps on increasing until it concentrates and then becomes constant.
Meanwhile, or as a consequence* (I'm not sure which, they don't explicitly say it), there is another current called drift current which is opposite to diffusion current where the electrons move from p to n under the charge separation created in $^1$ and holes vice-versa. This does not make sense to me. If the p side of junction had a negative charge, how could anymore electrons penetrate it to reach the other side and if we consider that this happens meanwhile, (while the diffusion current is concentrating to a constant value), then what is the driving force for the minority charge carriers to move (like that for majority was concentration gradient)?
Here's what I need to know:
a) if my explanation of how it works is correct regardless of what I make of it.
b) the answers to questions that I put in parentheses.
c) a resource to intuitively understand the topic.
d) an explanation of how the junction works if everything written above sounds gibberish to you.