They are not the same. They describe a change of state of matter by the addition or subtraction of thermal energy. The temperature may be the same, the change of state is not.
Yes, but not for all substances. Only water and some more. For example water. Water will melt at 0 degrees Celsius. Water will freeze at 0 degrees Celsius too.
Melting and freezing points are the same because a substance at a certain point can either freeze or melt. If energy is taken away from the compound, it will freeze. On the other hand, if energy is...