Is it permissible to ask for a longer life with the intention of doing good deeds, and is a person rewarded for their intention to do a deed that they were unable to perform?

A long life for a believer spent in obedience to Allah Almighty is a great good, for the Prophet, peace and blessings be upon him, said: "He whose life is prolonged and whose deeds are good." Similarly, a sincere intention to perform an act of obedience earns a reward for the servant, for he, peace and blessings be upon him, said: "And whoever intended to do a good deed but did not do it, Allah records it for him as a complete good deed." Sheikh al-Islam Ibn Taymiyyah said: "Whoever intended good and did what he was capable of, but was unable to complete it, will have the reward of one who performed it." Therefore, a sincere intention to memorize the Quran is hoped to earn its owner the reward of a memorizer of the Quran, but whoever is granted success in acting upon it will receive a multiplied reward that is not attained by intention alone.