Why when I raise my left up arm up to the sky do I get a really sharp pain that radiates from my armpit up my arm? (Vision&temple issues CRP high)

Nerve pull. You probably do not engage in regular exercise. Stretching the arm is causing tension on a nerve. You can address it by gradually raising your arms each day, multiple times and increase the level of raising. It would be good to engage in regular aerobic exercise for at least 150 minutes/week.