How can I become an actor?

I just realized today that jake gyllenhaal was only 19 when he played one of his most iconic roles as Donnie Darko and made such a huge name for himself and his acting career. I’m 19 and aspire to become an actor and seeing this made me feel like I’m behind, I want to be an actor more then anything but I have no idea where to start, does anyone have any advice where to start on acting?? What are the first steps, what are the best acting classes to get into