When you don't have any driver license, you need to pass the knowlege test to get learner license, and after several months you can take road test and get G7 license if passed. When you have Learner license, you can't drive alone and can't drive after midnight before sunrise.
If you already has license from China, you also need to pass the knowledge first, then you can take road test and then get G5 license.
In Vancouver, I did not heard any one that can get lower insurance by study at driving school. If you want to get discount, better prepare some paper work from Chinese insurance company.
You don't need a license when you buy a car though better you should had one. But you do need a license to drive it.
When I bought my car, I didn't have a Canadian license, I only have license from China.