Hi Usman,. Moving charged particles create a magnetic field, which exerts a force on other moving charged particles. Electrons have a property called 'spin' which causes magnetic fields to exert a force on them. read more
For the magnet's north pole to be attracted towards Magnetic North, the magnetic polarity of that location must be south -because unlike poles attract. So, the earth behaves like a giant bar magnet, with its south magnetic pole located at Magnetic North, and its north pole located at Magnetic South. read more
The lines of magnetic field enter at the south-type pole and exit at the north-type pole. Why they attract and repel each other is a long story that goes to magnetism as being a subset of electromagnetism, whereby considering the interaction forces of charged particles in relative motion. read more