According to the Insurance Bureau of Canada for a G1 driver there is no premium charged but the insurance company should be advised that there is a level 1 driver in the household. When the driver obtains the G2, the insurance company again should be notified. With your G2 most insurance companies will require you to be added to your parent's insurance policy since you are part of their household and now have more driving responsibilities with fewer restrictions while operating your parent's vehicles.

If your parents do not inform the insurance company of your G2 licensing status then it is likely that you will not be properly covered if you were to be in an accident in your parent's vehicle. As for driving a friend's car, in Ontario the owner of the car is typically responsible for anyone who drives their vehicle with permission so your friend will need to check with their insurer to see if you would be covered to drive their car.

Your friend will need to keep in mind that if you are covered by their insurer and you have an at-fault accident while driving their car, it will go on their insurance record and your friend will get the hit on their insurance premium. Insurance does not follow the driver; it goes with the car.