Okay, I don't know is the theme in the correct section, but I have a question.
I am 13 years old and I have eight pack, but my first pack [down to up]
doesn't seem developed enough..
So , my question is about a bar/normal training for eight pack to develop my first pack.

With 13 years you won't be able to develope an eightpack or any muscles properly, just wait couple of years and continue doing basic stuff

Actually, like I said I already have the eight pack , but the lower abs aren't as visible as the upper ones ^^

To make them more visible ----> diet, but belive me it isn't that good in your age ^^

Nah, it's not something that important, I just wanted to know, and I dont want to do any diets, cus my body isn't fat or something , just the lower abs arn't so visible..Anyway, I'll continue doing my basic trainings and see what'll happen.

if u've hit puberty then u can train if u ask me lol. but dont do anything stupid. keep it simple. and dont overtrain. at ur age it can be a b**ch.
for the eightpack.. well it seems ur lower abs need to get that pound of fat off them. so id suggest eating like u eat.. and eat alot, but move too. jogging and stuff. thats never bad