Can the people of Paradise go back in time to correct their mistakes, and will Allah fulfill for them everything that crosses their minds and that they were unable to obtain in this world?

Lifespans are in God's hands, and humans do not know when they will die. What is required of a believer is to prepare for death through repentance and performing righteous deeds. Sincere repentance transforms evil deeds into good ones. If a believer enters Paradise, he will attain everything he wishes for. However, no one returns to this world after entering Paradise; even a martyr's request to return to the world to be killed again is not granted.