Does a son's or daughter's learning of the Qur'an and Tajweed, and every righteous deed they perform, count as ongoing charity for a deceased parent?

Any righteous deed dedicated to the deceased will, by Allah's permission, reach them. However, what a child does for their parents will not reach them unless the child dedicates it to them. Allah Almighty has promised to unite the believer and their offspring who followed them in faith in Paradise, placing them in the same rank. He will elevate those with lesser deeds to match those with abundant ones, out of His grace. Your learning and memorization of the Quran, or any action you perform, are not considered ongoing charity (sadaqa jariya) for your father. However, you can dedicate to him whatever reward you wish from them. As for the question of whether someone who dedicates the reward of an action to another receives a similar reward, you can refer to Fatwa No. 48491.