Ākhirah is an Islamic term referring to the Afterlife.

It is repeatedly referenced in chapters of the Quran concerning the Last Judgment, an important part of Islamic eschatology. Traditionally, it is considered to be one of the 6 main beliefs of Muslims, the others including:

=> Tawhīd (Unitarianism),
=> belief in the angels,
=> belief in the Revealed Books (Scrolls of Abraham, Tawrah, Zabur, Injīl and Quran),
=> belief in the prophets and messengers, and
=> belief in predestination.

=> belief in Ākhirah (Afterlife)

According to the Islamic beliefs, God will play the role of the Qadi (Judge), weighing the deeds of each individual:

He will decide whether that person's Ākhirah lies in Jahannam (Hell) or Jannah (Heaven) on the basis of the weight of either good or bad deeds in comparison with one another.

The judgment doesn't depend upon the amount of deeds as much as it does on the will behind the deed, deeds are judged on the basis of the will behind it.

Jannah and Jahannam both have various levels.

The placement of a person may depend upon the extent of his or her good deeds. It is also said that God may forgive a sin against Himself but not against another human.

No religion except Islam shall be accepted:

The Bible, Gospels, Psalms and some other previous religious texts are said to be from God in Islam, but they are believed to have been edited to a great extent over time by people according to their own will. God has promised to keep the Quran safe from any such changes.

According to Islam, death is not the end of the life, but it is a transferral from this world to spiritual realm:

With the withdrawal of the spirit from the body, the soul's life in the Barzakh (Shadow Kingdom, a place where spirits of the physically dead abode until the Judgement Day) begins until the Day of Resurrection.

According to the deeds of the believer and disbeliever, their Barzakh differs.

Allah says in Quran, surah 2:154:

And do not say about those who are killed in the way of Allah, "They are dead." Rather, they are alive, but you perceive [it] not.