It varies from person to person, but the large hormone releases associated with puberty begin to fade beginning at age 18 and all the way up to 25 (and sometimes even older). New cellular growth continues somewhat longer.
This really depends on boys. Since everyone is different there really isnt a definitive answer. But on average. Boys start puberty anywhere from age 11-14. usually stop by the time they are 19 or 20
Puberty for boys typically ends once they turn 21. At this point they are finished growing and all their hair growth is in place. Hormone levels start to level out and acne clears up.