Boys fifteen years old can shave, if not a lot of premature shaving is not recommended.
Boy 15 years old long beard is a normal physiological phenomenon, due to this time in adolescence, is also the peak growth and development, hair follicles are also developing and perfecting. If the beard is too long, affecting the normal life or the external image of the beauty, you can scrape off the beard. But shaving should be careful, do not hurt the skin, to avoid causing infection.
At the age of 15, the beard is mostly some black fluffy hairs, which are relatively soft. If it doesn’t affect your life too much, it is recommended to shave after puberty. Shaving too early may lead to irritation of the hair follicles, resulting in folliculitis and so on.
In conclusion, if the beard affects your life as well as your image you can consider shaving, but be careful to do it in the right way to avoid hurting your skin.