A boil is a skin infection that start in an oil gland or a hair follicle. The skin turns red in the infected area and then a tender lump develops. Within week, as pus collects under the skin, the lump starts turning white then it becomes an abscess.
Either way works, but it’s easy to overcook shrimp when you boil them. To prevent this, reduce the water to a simmer before putting in the shrimp. Check them frequently...