What is the religious interpretation of what the questioner sees and hears from his mother's image, and what is required of him to do, taking into account that the soul ascends to its Lord?

After death, a person transitions to an intermediate, barzakh (definition) life, separate from the worldly life. The soul cannot return to this world to communicate with the living. What you are experiencing might be from the qareen (jinn companion) who was associated with your mother. Your duty towards your parents is to supplicate for them, honor their friends, seek forgiveness for them, and maintain the ties of kinship that are only maintained through them.