Is a deceased person considered repentant for having turned to fasting and listened to a lecture about those who abandon prayer? Are charity, supplication, and Hajj permissible on his behalf? Is it permissible to perform fasting and prayer on his behalf?

Seeking forgiveness for this deceased person and supplicating for mercy and forgiveness for them is permissible, and there is no harm in dedicating the reward of righteous deeds to them, such as charity or fasting. As for the prayers they missed, they cannot be made up on their behalf; rather, forgiveness should be sought for them. Regarding making up obligatory fasts on their behalf, there is a difference of opinion, and the preponderant view is that it is permissible, based on the Prophet's (peace be upon him) saying: "Whoever dies and has fasts due upon him, his ولي (guardian/next of kin) should fast on his behalf." If no one fasts on their behalf, a mudd of food should be given to a poor person for each day, and this feeding is obligatory if they leave behind an inheritance.