I have a friend with lymphocytic chronic leukemia. what are the best superfoods to help with immune system and chemotherapy?

Be a friend: I know you want to help your friend. However, food choices aren't key to managing cancer or the side-effects of chemotherapy. You'll be doing much more good if you help your friend with daily tasks, transportation, getting to appointments, and so forth, than telling her what she should eat. Her physician has already discussed what matters. Be a real friend, not a lay dietician. Best wishes.