When I got my license in Ontario back in the late 80's, early 90's, anytime after you turned 16, you wrote a written test and got the learner's permit, also known as a 365 because it was good for one year. This allowed you to drive with a licensed driver in the front seat, next to you. That driver must be capable of driving so couldn't be over the legal limit for alcohol. Within that year, you did your road test to get your full license, no restrictions.
Now, we have what is known as graduated licensing. At 16, you can write a written test and get your G1. You are then permitted to drive with a licensed driver in the front seat with you. I think that driver has to be over the age of 21. You can have absolutely no alcohol in your system, you can't drive on 400 series highways (freeways in the States), you can't drive between certain hours, etc. Once you've had your G1 for a while - at least 6 months but not more than a year, I think - you take your road test to get your G2. Which is still somewhat restricted. You don't need a licensed driver but you still need a BAC of 0; I think there might be other restrictions, too. Within 5 years, you have to do your road test for your full license or G. If you are still under 21, you can't have any BAC until after 21 but that is the only restriction.
We discovered another little wrinkle. My nephew had a small accident with his G2 license. Until he gets his G license, he doesn't start recording accident free time. Which is significant because you don't get an insurance break until you've been accident free for 6 years. He's doing his G road test next week. Hopefully, he'll pass and will start the clock ticking. My brother pays the insurance, my nephew has to pay the increase in insurance and had to pay the deductible from the accident repairs. Which everyone thought was reasonable.