Hello I have driven the Thunder bay leg to Edmonton many times.
From Toronto, if you do not want to go through the USA you will have to grab HWY 17 to get around the lake through to thunder bay and onto Winnipeg. This is a single lane road all the way but very scenic for sure! Plan your stops!
From Winnipeg I would take the #1 hwy all the way to Calgary. It is Twinned all the way, easy but boring drive all the way. You can stop at most Walmart's and stay overnight, They are right beside the hwy most times.
Then take the twinned hwy #2 from Calgary to Edmonton.
2cnd option is take #1 from Winnipeg to Regina. Then take #11 north which is twinned to Saskatoon and then #16 which is twinned to Edmonton.
They both take about the same time
I would stay off #16 from Portage to Saskatoon as it is single lane most of the way and rough in spots!
Hop this helps!
Clandeboye , Manitoba