study in canada

In Toronto, grade 12 is the last year in high school before going to college or university. Since you are born in Canada, for no doubt you are resident of Canada and could receive free highschool education overthere.
The first thing you have to do is send an email to school board and ask for the necessary document they need to register
http://www.tdsb.on.ca/

Usually, transcipts or report card from your school is helpless since they will consider english is not your first language and you might not be able to start with the same grade as you had expected. If you have pass HKCEE, it will do a great help since it is an accepted document and they could give you credits on many subjects and you do not need to study it again. Most people will still need to take 6 credits before they could get the High school diploma in Ontario after they have completed F.5 in HK.
Since you are grown up in HK, you've better take the TOFFEL or CAL test to prove your english standard, otherwise, you might need to take the English as Second Language courses before you could attend the regular courses in high school.

Also, they will need you to take tests on Eng and Math in order to get the grade appropriate for your level overthere ( but don't worry, it's very easy for you if you already got up to F.5 in HK)

It might be a bit late for your application if you want to start your study in Sep 07. In my opinion, you might now start to prepare to study at next year. I suggest you ask somebody living overthere to go to School Board and get the information for you.

Good Luck

Well, if you are Canadian why you apply as an international student?
Cause you have not any advantage if you being international student.

If you have the address at Toronto, then you are supposed to enter either one of the High school within your home address school board. So, you don't need worry about those interviews or application form... regular process only, they have to accept you if they have space avaliable.

For the transcipts, you better prepare the related courses decription about our Cert. Level. Like Maths, EPA, Chem, Phyics, Bio..etc.
Cause it is probably required for claiming the credit. That's was my exprience when I claimed the transfer credit from the College before.