As stressed before, an electron is one quantum (formally it's a one-particle Fock state). This means it's neither a classical particle nor a classical wave but can only described by quantum theory. There's no simpler way to describe it that is entirely correct. The wave-like and particle-like properties are only consistently described by quantum theory, and you cannot describe it in some simpler way.
You cannot say, the electron takes a certain way or that it takes every possible path at once. What you calculate with the Schrödinger equation or, equivalently, with the path integral is a socalled propagator, which is a mathematical description how the state (a highly abstract mathematical object) evolves in time, given the state at some initial time and the interactions (forces) of the particle with the experimental setup (in this case with the double slits). The result is a probability distribution that the electron makes a mark on the detection screen. You an make this probability distribution visible by performing the experiment very often with the same initial state of each electron and the same experimental setup. All we can say is that up to know the predictions of quantum theory are confirmed by the so made observations. You cannot expect more from the natural sciences than such a successful description of objectively observable facts about (certain aspects of) nature. Particularly, it never answers and also never aims to answer the question, "what's really going on". The reason is, that you cannot even precisely define, what you mean by this question. It's highly subjective, depending on your personal experience in life. It takes time to get used to the very unfamiliar way of thinking when it comes to the realm of nature requiring quantum theory to describe it. The intuition is due to quite abstract ideas, and you can only grasp its meaning by looking at it in different applications to get a kind of intuition for these highly abstract ideas.
