Salam envyroses
*According to the quran what is the reason we die? (please show me the surrah that proves)
According to Islam, this life is a test for the hereafter. Allah has created life to test who is good, obedient and who is bad, disobedient. Death is simply the end of our test. As the Quran says
الَّذِي خَلَقَ الْمَوْتَ وَالْحَيَاةَ لِيَبْلُوَكُمْ أَيُّكُمْ أَحْسَنُ عَمَلا وَهُوَ الْعَزِيزُ الْغَفُورُ
He Who created Death and Life, that He may try which of you is best in deed: and He is the Exalted in Might, Oft-Forgiving;-
Al-Qur'an, 067.002 (Al-Mulk [The Sovereignty, Control, Dominion])
Hence He tests us through our life and death.
Hope I helped.