How can we save a young man who claims that the Qur’an is not a miracle and that God is unjust, and has begun to lean towards atheism?

The miraculous nature of the Qur'an is clear and established. Allah challenged the Arabs with the entire Qur'an, then with ten surahs from it, and then with a single surah, but they were unable to produce anything like it. No one throughout history has been able to imitate it, fulfilling His (the Almighty's) saying: "Say, 'If mankind and jinn were to gather in order to produce the like of this Qur'an, they could not produce the like of it, even if some of them were assistants to others.'" As for the claim of Allah's injustice, it is refuted both by Islamic law and by reason. Allah is the Just, and He wrongs no one. He has forbidden injustice upon Himself and commanded His rulers to be just. To save the young man, it is advised to supplicate for his guidance, engage him in dialogue with wisdom, teach him, debate with him in the best manner, remind him of Allah's verses, lend him beneficial books and tapes, and connect him with righteous company.