Why do you imagine for a second that this will be better?
If you run away, you'll be homeless, you won't be able to attend school (thus compromising your future), you won't be able to work, you'll be homeless....
While currently, your life isn't ideal, but you have a home, heating, clothes, food, education... And you can move out at 18.
Running away to LA is like running away from thing you face in life..
You are only 15 and now you cannot face the things you have now so what is the difference between facing your life in LA?
Here's some tough love for you.
I live in L.A.
L.A will eat you up and spit you out.
You're life will be ruined before it gets started.
Do what you want but that's the truth.
Finish high school (or whatever its called in Canada) and when you are 18 see if you still want to come to L.A. I got that advice when I was 14 and it was the most valuable advice anyone gave me at that time. L.A. is pretty wonderful, but you need a lot of money to live comfortably here. Good luck!
You are 15... running away goes through every kid's mind every now and then. Do not run, because you are not prepared. Living in LA is not what the tv shows and movies make it seem. Not to mention you are a minor, and you do not have a passport. You need to cross the border... OBVIOUSLY to get into the United States, and you need to cross at least Washington and Oregon.
What you do need to do, is change your outlook on life. Is being a runaway really worth it?