Belief in hereafter
It is Fard upon every Muslim to believe in the Hereafter (Aakhirah).
Our life in this world is a test and only for a short period of time.
We live in this world to prepare for the Aakhirah.
We have tests and examinations in the school and in the madressah to see who gets good results and who performs poorly. In like manner, Almighty Allah will put us to the test when the world comes to an end. We will be asked questions about how we spent our lives, what good deeds did we do and what bad deeds did we commit. If we pass the test and Almighty Allah is pleased with us we will go into Jannah. But if we fail, we will be thrown into the Fire of Jahannam (Hell).
To prepare ourselves for the Aakhirah we have to obey the Commands of Almighty Allah and our Nabi Muhammad
Those people who will go into Jannah will live forever in happiness, while those who are meant to remain in Hell forever, will be surrounded by punishment.