I'm 19 years old, a college student in Malaysia. As we know that, all things (any matter) happen by Allah; will. why did He create man that have kind persons and cruel persons. Why He don't create or make all mankind obey His order and go to the Heaven. Please give details statements from Hadith or al-Quran.

All perfect praise be to Allaah, The Lord of the Worlds.  I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.

The Muslim should believe firmly that all things are predestinated by Allaah and that He should not be asked about what He does.  Indeed there is a great wisdom behind every creation of Allaah. Allaah informs us in the following verse of the aim for which the person was created, He Says: {And I (Allaah) created not the Jinns and the humans except they will worship Me.}[Quran: 51:56] Allaah promises those who obey his orders of His Paradise and of His gratification. He warns those who disobey Him of His Hellfire and His Anger. Allaah gives the person the will and the volition to choose between belief and disbelief, He Says: {…. Whosoever wills, let him believe and whosoever wills let him disbelieve.}[Quran 18: 29] He also Says: {Verily, we showed him the way whether he be grateful or ungrateful.}[Quran: 76: 4] So, the people as well as the Jinns have been divided into believers, unbelievers, righteous, wicked, oppressors, oppressed, and so on. If Allaah had wanted to guide all the people, He could have done so as He Says: {Verily, We showed him the way, whether he be grateful or ungrateful.}[Quran 76: 4]  But there is a great wisdom behind the existence of the sinful, the unjust and the unbeliever, as they are means of trial and testing to distinguish the contented and forbearing ones from the pessimistic and restless. This is the reason messengers were sent, books were revealed, Jihaad was prescribed and D'awah (the call to Islam) was established and ordered. The existence of the unjust and the sinful is similar to the existence of the hot and the cold, diseases, illnesses and various other trials. If all people were good and obedient to Allaah and if this life was free of sorrow, pain and trials, then there would not be a difference between this life (the life of trial) and the Hereafter (the life of punishment and reward) and Paradise would have been the same as this Life, and there would not have then been a wisdom behind the creation of Satan and what happened between him and our father Aadam . To conclude, we are all called to abide by the orders of Allaah and to follow His messengers, and whoever refuses to do this will regret it.  The Prophet, sallallaahu ‘alayhi wa sallam , said: “All the members of my Ummah (nation) will enter Paradise except those who refuse.”  Someone asked, "O Prophet of Allaah, who would refuse?"  The Prophet, sallallaahu ‘alayhi wa sallam, replied: “Whoever obeys me will enter Paradise and whoever does not obey me he has refused (to enter Paradise)."

Allaah Knows best.