Oh, okay, I now have a better understanding of your route.
From Calgary to Banff and Lake Louise you'll be on the TransCanada Highway (Hwy #1). I provided a TransCanada Highway website in my previous post.
From Lake Louise to Jasper, you'll drive the Icefields Parkway (Hwy #93).
A while back krp329, who is TripAdvisor's Local Expert for Jasper, posted this great website about the Icefields Parkway:
From Jasper to Prince Rupert you'll be driving the Yellowhead Highway (Hwy #16). I have not been to Prince George, Smithers and Prince Rupert myself. However, here is a website about the Yellowhead Highway:
The good thing about the route you'll be driving is that, once you're on the correct road out of Calgary towards Banff, it'll mostly be a "no brainer" to stay on the correct route. Compared with Europe, Western Canada has very few roads.
The route you'll be driving will be like a giant letter H lying on its side. Calgary is at the bottom right hand (southeast) end of the horizontal H. You will drive westwards along the lower line of the horizontal H, through Banff to Lake Louise.
Just after Lake Louise you will need to turn northwards onto the Icefields Parkway till Jasper. The Icefields Parkway is the short line that joins the two long lines of the H.
Then from Jasper you'll drive westwards to the top left hand (northwest) end of the H, which is where Prince Rupert is.
When you leave Jasper you'll drive westwards on the Yellowhead Highway (Hwy #16) to Tete Jaune Cache. There you will have an opportunity to turn northwest onto what is known as the North Yellowhead Highway (which still goes by the number 16). that is the route you want.
Your other option at Tete Jaune Cache, which is the one that you do not want to take, is the South Yellowhead Highway (Hwy #5). That would be the one that would take you to Clearwater, Kamloops and Hope, but that is a route that you have rejected.
Once you turn onto the North Yellowhead Highway (Hwy #16) at Tete Jaune Cache, you'll go through Dunster, McBride and some other small towns until you get to Prince George which, as I understand it, is the largest of the towns in that region of British Columbia. But it's not as if you'll have opportunities to get lost. If my experience of other parts of Western Canada is anything to go by, all you'll need to do is follow the road, and you'll end up in Prince George. You simply will not have any opportunities to take wrong turns.
In Prince George you'll have an opportunity to take a wrong turn. It would be a mistake to turn north onto Hwy #97. That would take you on a somewhat winding road which, after a LONG drive, would bring you to Dawson Creek.
In Prince George it also would be a mistake to turn south onto Hwy #97. If you did that you would drive through Quesnel, Williams Lake and some other towns, until you reached Hope, which is not very far from Vancouver.
If you can avoid those two mistakes in Prince George and keep going westwards on the Yellowhead Highway (Hwy #16), you'll go through Vanderhoof, Smithers, etc., and end up in Prince Rupert.
Between Prince George and Prince Rupert there are a handful of opportunities to turn off onto minor roads that lead to much smaller towns. Again going on my experience of other parts of Western Canada, it will be very obvious to you that those roads are very minor compared with Hwy #16. I am sure there will be no doubt in your mind, from the width of Hwy #16, from sign posts, and from other clues, which road you're supposed to stay on.
I always travel with a map and a compass. I find a compass to be useful in strange cities, where I sometimes become disoriented (for example, when I've just emerged from an underground train station or something like that). I also find a compass to be useful in some circumstances in rural and wilderness areas. For example, it might be an overcast day, so I don't have the sun as a reference point, and I might be surrounded by forest. In a case like that, a compass can come in usefully.
Hope that helps.