Performing Arts students and professional actors?

[SJSlytherin]

So i have done GCSE Drama for 2 years, and have developed so much love for this subject and acting overall that i want to continue doing it in my future.

However, everyone in my family has top careers (mum is an arcitect and dad owns electricity firm, aunty is a prosecuter, etc etc)

So they expect me to do as well as them, like journalism which i concidered too.
I mentioned that i wanted to act, and everyone was immediatly against it, saying things such as that acting wont be good enough for me and all off that crap.

I have just managed to persuade them to let me study A Level performing Arts.
Now what else can i do in my free time, any good excellent Acting schools or theatres i can work in. It doesnt have to be acting, just being part of the environment?
Help please!
BTW I LIVE IN LONDON