What does Islam say about the woman or man who colored his hair, and for a young man who has a white hair and he wants to make color, is it forbidden (Haram)?

Praise be to Allah, the Lord of the World; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

Basically dying one's hair with black colour is not permissible. A Prophetic Hadith narrated by Imam Muslim about the hair of Abu Bakr's father which was white, reads: "Change this (its colour) but avoid black" .
The above ruling applies to the one whose hair becomes white naturally, without any trouble (abnormalities) such as illness or the like. Under the latter conditions, one may dye hair black colour because this act is considered as returning the original colour rather changing its nature. Thus, dying with black colour is more suitable for a youngster in his early years of youth.
Know that there is disagreement among the companions of the Prophet (Sallallahu Alaihi wa Sallam) concerning the matter of dying hair black colour without any trouble. Some of them believe that it is permissible and some of them do not approve it. But the above-mentioned opinion is the safest and preponderant one.
There is no disagreement about dying hair with any colour except black from the above Hadith.
Allah knows best.