How would i become an actor ? ( 15 years old atm )?

so basically , i have always had a knack for performing and acting , and i feel i could get further with it. Im in the UK , year 10 at school . I missed out on taking drama as a subject ( complications and stuff ) but i would love to carry it on ... obviously i don't have experience so would i have to sign up at a drama school and take it from there .... ?