1. Where does the electromagnetic force of the magnet come from? Let's do something scientific. Atoms consist of positively charged nuclei and negatively charged electrons. Inside the atom, electrons are constantly moving around the nucleus, and they are also constantly rotating. Because the moving charge will produce current and magnetic field, the movement of electrons will produce magnetic field. Usually, the attraction of a magnet is not a force, but a field, and a magnetic field has energy.
Second, in most substances, because the electrons move in a chaotic way, the magnetic effects produced by the electrons cancel each other out, so they are not magnetic on the macro level. However, there is a strong interaction between electrons in ferromagnetic materials, which is called exchange coupling. This makes them produce a unified magnetic field domain, which spontaneously diffuses in a small area, which we call magnetic domain. Defying gravity, but using the potential energy of magnetic field, which is the source of energy. Magnets have the potential energy of a magnetic field, but iron or other things don't. This is the difference between a magnet and iron. When the magnet loses its potential magnetic field energy, it also loses the energy source of defying gravity's falling.
Third, for ferromagnetic substances, it has many magnetic regions. Generally speaking, these regions are not arranged in the same direction, so they do not have overall magnetism. However, if we put ferromagnetic materials in a strong enough magnetic field, the magnetic domains will be pulled in the same direction by external forces. In this case, the ferromagnetic material is magnetized and becomes an ordinary magnet. Even if the external magnetic field is removed, according to quantum theory, this magnet stuck to the refrigerator for decades is the source of strength to overcome gravity.