God has said in the Quran:

{ Those who have disbelieved and died in disbelief, the earth full of gold would not be accepted from any of them if it were offered as a ransom. They will have a painful punishment, and they will have no helpers.} (Quran, 3:91)

So, this life is our only chance to win Paradise and to escape from Hellfire, because if someone dies in disbelief, he will not have another chance to come back to this world to believe. As God has said in the Quran about what is going to happen for the unbelievers on the Day of Judgment:

{ If you could see when they are set before Hellfire and say, "Would that we might return (to the world)! Then we would not reject the verses of our Lord, but we would be of the believers!" ) (Quran, 6:27)

But no one will have this second opportunity.

The Prophet Muhammad (pbuh) said: { The happiest person in this world of those doomed to Hell on the Day of Judgment will be immersed once in Hellfire. Then he will be asked, "O son of Adam, did you ever see any good? Did you ever experience any blessings" And he will say, "By God, no, O Lord!"}¹