Heaven
Question :

In Heaven, will each person own an individual kingdom to govern as a king or queen or will they all live together in one kingdom?

Answer :

Such details are not mentioned in religious texts but it is reported that the believers will meet. Almighty Allah said: "And we remove whatever rancor may be in their breasts. As brethren, face to face, (they rest) on couches raised." (Quran 15:47) One should believe in the overall existence of the gardens of delight that Almighty Lord promised to His righteous slaves. May Allah consider you and us amongst them.

Hell
Question :

Why was Hell created, when Almighty Allah is a merciful and forgiving Lord?

Answer :

Almighty Allah is wise and just, as well as merciful and forgiving. As His mercy results in forgiving and goodness and rewarding the obedient people with great rewards and the eternity in heaven, His wisdom results in judging the wrongdoers and punishing them. One of the characteristics of such wisdom is the creation of fire and making people fear its torture and warning them from it and punishing the criminals with it. May Allah grant us all refuge.

Barzakh
Question :

Does a believer have to face Barzakh after death? Or can he get the intercession of Imam Ali (peace be upon him)?

Answer :

It appears from the narrations that Almighty Allah may punish the sinner because of his sins in this life by subjecting him to several hardships that he faces, including poverty, illness and the like, in order to reduce the punishment after death. The sinner might also undergo suffering as a form of punishment after his death, in the stage of Barzakh. At the same time, he might be given the chance of obtaining the intercession of the Ahlulbait (peace be upon them). In some narrations, the Prophet and the Imams (peace be upon them) visit the believer when he is dying to ease the hardship of death and to give him the good tiding of Heaven. Mohammed bin Hanthala asked Imam Jaffer Al-Sadiq (peace be upon him) that some of the Shia companions stated that the best time for the believer to see the benefit of his belief in the Imamate of the Ahlulbait (peace be upon them) is when he is about to die. Is this true? The Imam (peace be upon him) replied: Yes.

Paradise & Hell
Question :

Is it correct that a Muslim goes to hell and gets his punishment in hell for the bad things he did, and after his punishment he goes to paradise for his good deeds?

Answer :

It is reported in some narrations of the Imams of the Ahlulbait (peace be upon them) that a believer does not stay in hell for eternity, but is accounted for his sins in the grave or on the Sirat or by other means.

Going to Heaven
Question :

Is it necessary to be a Muslim in order to go to heaven? Can non-Muslims go to heaven, and what about people from other sects?

Answer :

There is no doubt that to be accepted into Paradise one should be a Muslim. Almighty Allah said: "And whoso seeks as religion other than Islam it will not be accepted from him, and he will be a loser in the Hereafter" (3:85). Among the perfections of the Islamic faith is the belief in the Imamate of the Ahlulbait (peace be upon them). One of the fundamental of the true faith is the belief in their guardianship (wilayah). The individual will be asked of this belief on the Day of Judgment, as well as his good deeds and worships.

Non-Muslims
Question :

Surah Baqarah, verse 62, states: "Verily those who believed, and those who are Jews, and the Christians, and the Sabeans - whoever believes in Allah and the Last Day, and does good deeds, shall have their rewards from their Lord. They will have nothing to fear or to be grieved for."
This verse clearly indicates that non-Muslims can enter Heaven and attain salvation in the Hereafter. A person who has been raised in remote and distant places cannot learn about Islam and its teachings, so how can he go to Hell? This will be against the justice of Allah Almighty.
Please could you address these issues.

Answer :

There is no doubt that Almighty Allah, after He sent the Messenger and asked people to believe him and act upon the ruling of the religion, has established the evidences to prove the truth of the message, so He will reward those who obey and accept the call, and He will judge those who did not accept and did not have an excuse. As for those who had valid excuses for their non-acceptance, like the lack of available evidences or because of lack of sanity, Almighty Allah will judge them accordingly, since He "wrongeth not even of the weight of an ant" (4:40). However, we cannot determine those who are excused and those who are not, and one should search for the right religion. Allah Almighty knows the circumstances and the intentions of His slaves. We, as humans, are only aware of the apparent behavior of people.
The verse that you were referring to, that talks about the believers in previous religions, is interpreted in many religious texts to be referring to the believers of those religions before the emergence of Islam. Some narrations indicate that the subject of this verse are those like Salman the Persian and similar believers who believed in undistorted religions before Islam.
This is the very clear message from the verse, which is consistent with the teachings of the rest of the Quran. The interpretation that you have chosen is inconsistent with the message of the rest of the Quran.