(11-14yrs)about puberty

1.When I am changing clothes in the toilet with other boys,I saw their penis no hair but the size of the penis is more longer than me,Y ? How can I improve ?

2.Actually I am 13 yrs old and suppose already started puberty,but I am confused about the size of my penis and I want to compare with my frds,but it is very embarrass to ask something about this,anyone hav a reference about the size of penis (for 11-13yrs old boys) ?