Can the reward for a son's recitation of the morning and evening supplications (adhkar) or the sleeping supplications reach his elderly mother who cannot read or write, and can these supplications protect her from harm?

If you recite the morning, evening, or pre-sleep remembrances (adhkar) and dedicate their reward to your mother, who is unable to recite them herself, then the reward will reach her according to some scholars. As for reciting the adhkar with the intention of memorizing them, this can be achieved by reciting them while blowing gently over them (nafth), just as Aisha used to do with the Prophet, peace and blessings be upon him. It is advisable for the mother to learn to recite these adhkar herself.