Luffy, also known as Monkey D. Luffy, is the protagonist of the popular anime and manga series “One Piece”. The series follows Luffy’s journey as he sets out to become the Pirate King and find the ultimate treasure known as One Piece.

In the first season of the anime, which covers the East Blue arc, Luffy is introduced as a 17-year-old boy from the East Blue region of the One Piece world. He is shown to have a distinctively rubbery body due to eating a Devil Fruit called the Gum-Gum Fruit, which grants him the ability to stretch and manipulate his body like rubber.
Throughout the first season, Luffy forms his own pirate crew, known as the Straw Hat Pirates, and sets out on a quest to find the legendary treasure known as One Piece. Along the way, he and his crew encounter various other pirates and factions, and engage in battles and adventures as they seek to become stronger and achieve their goals.
It is important to note that the first season of the One Piece anime covers a number of different story arcs, including the Romance Dawn arc, the Orange Town arc, and the Syrup Village arc. Each of these arcs introduces new characters and challenges for Luffy and his crew, and helps to establish the world and mythology of the One Piece universe.
In terms of the age of the first season of the One Piece anime itself, it was first aired in Japan in 1999, and consists of a total of 61 episodes. The anime has since been adapted into multiple seasons and movies, and remains one of the most popular and beloved anime series of all time.
In conclusion, Luffy is introduced as a 17-year-old boy in the first season of the One Piece anime, which covers a number of different story arcs as he and his crew set out on a quest to find the legendary treasure known as One Piece. The first season of the anime was first aired in Japan in 1999, and has since become a beloved and enduring classic of the anime genre.