What is the ruling on prayer and reading Qur’an for a young man from whom semen was discharged during his sleep, and he did not know about it until the following day, after he had prayed, fasted, and read Qur’an?

Scholars have unanimously agreed that the prayer of a person in a state of major ritual impurity (junub) is invalid due to the absence of a condition for its validity, namely ritual purity (tahara). They cite the Almighty's saying: "O you who have believed, do not approach prayer while you are intoxicated until you know what you are saying, nor while junub, except those passing through, until you have washed [your whole body]." The majority holds that it is forbidden for a junub person to recite the Quran, while Ibn Abbas and a group of scholars permitted it. As for one who prays or recites while unaware of being in a state of janaba, there is no sin upon them, but they must repeat the prayers they performed while junub. The fast of a junub person is valid by scholarly consensus because purity is not a condition for its validity.