QuestionWhat are the pimple-like bumps around the groin?
If the bumps you are referring to are not red and inflamed looking, then most likely they are bumps caused by hair poking up through the skin. Since the skin on the penis and scrotum is thin, the skin around the hair shafts is pulled upwards as the hair grows.
Some boys have a condition known as Fordyce's spots. These are small white or slightly yellow lumps on the penis itself that cause no problems and require no treatment. While it is known that the oil glands for the hairs are involved, the cause is unknown.
If the bumps are red and itch, then you may have contracted a fungal infection commonly called "jock itch." It is usually curable with an over-the-counter antifungal product.
Anything sore or inflamed should be seen by a doctor to make sure that you have not contracted a serious skin disease.