Is there repentance for a person severely afflicted with obsessive compulsive disorder who fears harming a specific individual, and what should he do to control this obsession, and what supplication should he say and how many times should he repeat it to avoid harming a specific person?

Obsessive thoughts about killing or harming someone with the evil eye do not entail a legal ruling or sin. Even if such a thing were to happen, there is no sin upon you as long as you did not intentionally cause harm. If envy leads to death, there is a difference of opinion regarding the obligation of retribution (qisas) or blood money (diyah). However, the preponderant view is that there is no qisas, no diyah, and no expiation upon the person who cast the evil eye if they admit to causing death with it, because they are not considered a destroyer, and the ruling does not apply to matters specific to certain individuals. Completely ignore these obsessive thoughts and do not dwell on them. There is no religious proof for repeating adhkar (remembrances of God) a specific number of times or throughout the day to ward off the evil eye.