A: In a more perfect world we would each be born healthy and with five good senses fully functioning. But the world is not perfect. Your desire to be of help to others is compassionate but it would be well to examine your reason for wanting to be a healer. Consider that one of the decisions Jesus made before he entered into his public ministry was that he would not employ any superhuman powers.((136:8.1)
Although miracles occurred during his ministry they were not pursued purposefully, with rare exceptions. Jesus counseled many times about the futility of employing "signs and wonders" to entice people into the Kingdom. You may remember that, many times, even those who received healing from Jesus refused to follow after him, and many times, did not even thank him. Healing is not a reliable way of bringing others to God.
Sometimes we can heal ourselves of psychosomatic infirmities and sometimes we can appear to heal others by engaging them to heal themselves, but most displays of healing are fraudulent. It's not one of the "powers" humans use to better their lives. Rather than wishing to heal your friend's child of blindness your influence might be more valuable by compassionately enriching this child's life."