I have a very bad Eye condition which isn’t curable. How can I Improve My Vision naturally by foods, exercise?

I have a bad eye condition known as renitis pigmentosa which makes the eye worse overtime. Im hoping to obtain some knowledge on what I can do as a teen to slow this process down by eating certain foods, working out, or exercising my eyes.

marijuana improves Eyesight

Be Thou My Vision Tutorial / Lesson for the Recorder (notes given at the end of the video)