Freshman 15 does not apply when you live at home in most cases. I actually lost 10 pounds while living at home, due to my tendency to skip meals while outside or studying. Don't do that either. Eat healthy, and eat your vegetables (seriously). Go to the gym once in a while, or play some intramural sports.
Most freshmen cannot handle living outside for once and go crazy on the ramen, cheap crappy microwave food and booze. Drinking a shit ton of alcohol itself will in itself, fuck with your body, especially if you're not used to it.
And if you go to a school in Canada, it's not as expensive as American ones. Therefore, go to a university, but go to a school like SFU where they let you have the freedom of going into whatever major you want and take whatever course you want. All that matters is that in the end, you have the pre reqs for the degree.
And please, don't bring your fucking high school drama to university. No one cares, and people will despise the fuck out of you for it. Especially if you make friends with 3rd or 4th year students. If it's about "OOOHH I CANT ASK OUT THIS GIRL, SHE'LL REJECT ME" or some shit like that, get over it, ask her out, or move on. You'll meet plenty of women at university, especially if you get involved in clubs and societies. I've seen kids do that, and I honestly thought they left that at high school. Apparently not.
That being said, you'll meet some great people in university. I've met friends at university that I never thought I'd ever meet. Some of the friends you meet here, will be your good buddies during your undergrad and your adult lives. Get out and meet these people. Your life will become that much more interesting.
Study hard. You're not hot shit. There are people from countries that you've met for your first time, and there will be kids who will beat you down intellectually and grade-wise. As long as you study, and keep up with your class work, you'll be a much happier person, and not lose that scholarship you worked so hard in high school for.
Many professors teach mainly because their tenure depends on it. That being said, there are professors who love your company, and your questions. I spent my Tuesday mornings in my physics professor's office asking for help on various physics stuff, and I've gotten to know him very well. He also bumped my grade, and I'm pretty sure the only reason I did well in his class was because I came during office hours. Professors are also vain; they love it when you're interested (or pretending to be) in their research. And some of the stuff they do is pretty awesome. One is developing a hydrogen based engine, that's more fuel efficient. Another is doing medicinal inorganic chemistry. Very interesting stuff, and it'll hopefully give you some sort of direction on what you want to do with your career.
I'm in the arts and social sciences faculty and I'm thinking of majoring in either history or humanities, but I'm also interested in geography and geology, so I'm not really all the sure yet.
I'm getting an entrance scholarship as far as I know, so that's always good.
UBC is pretty far away from me, at 1 - 1.5 hours on the bus, and I absolutely fell in love with SFU's architecture when I first visited there, so that was actually a pretty big influence on my decision.
Take a good variety of courses in your first year. You probably don't know what you want to do with your life at the moment, and I find alot of Arts students change their majors frequently, unless you're set on what you want to do.
Entrance scholarships are always good. Hint: maintain a 3.67 GPA and you'll get scholarship each year without applying. I'm getting 770 dollars out of 2000 paid for, because of it.
Architecture? I hope you're kidding me. That place looks like fucking Alcatraz. It was designed by a guy who designs prisons. Blusson Hall looks nice, and modern, and the AQ isn't bad. Otherwise, it looks depressing, especially in the winter, where in the fog, it looks like the bus is taking you to prison early in the morning.
UBC is also 1-1.5 hours away from me. I'll be commuting next year, and hopefully move out in third year.