A physical change does not make a new substance. If the change is reversed, the material recovers its original properties. Changes of state are physical changes. When water boils and the steam is cooled, the liquid that forms is the same water, with the same boiling point as before. Melting wax and then letting it freeze gives the same wax back.
Dissolving is also physical. Salt dissolved in water can be recovered by evaporating the water, and it is still salt.
In a chemical change new substances form with different properties. Burning wood makes ash and gases, and iron rusting makes a new compound. These changes cannot easily be reversed, so the original properties do not come back.