Do some people with high cholesterol live normal lives, or do they all die young from clogged arteries?

Depends. Cholesterol only accounts for one part of heart disease and there are patients who have high cholesterol who have not had premature death. The most important part of high cholesterol is understanding that you have to eat better, exercise and take supplements or medications. Eat lean protein, more plants (7-9 servings/day), good fats, whole grains and avoid refined sugars.
Normal. High cholesterol is only one risk factor. Smoking, diabetes, hypertension, genetics, and age are other factors. Since there's nothing that can be done for the last two, excellent control of the first 4 is crucial. All cholesterol can be lowered, even if not normalized. I've seen many pts >80 yo with high cholesterol. Good life style with normal weight and healthy diet can mitigate hi cholesterol.