begin to study photoshop

on first day, i begin to use photoshop for my lesson but i dont clearly understand about it. I just see it before when my brother use it for his job , i feel it is interesting and i want to learn it. But i dont learn it after i see because i'm busy for learning other subject. When i see everyone in my class who use it quite expert. And i want to same to them so maybe i try to learn hard about it.