Here is the route of the TransCanada highway from east to west:
Leaving the Alberta border, you have a full day of driving through mountain ranges. You pass through Yoho National Park to Golden, and cross the Rogers Pass through the Selkirk and Monashee Mountains. As you descend into the Interior of BC you arrive at Revelstoke, a city on the banks of the massive Columbia River system. From there, the highways winds westward into the pretty Shushwap Lakes region, and the towns of Sicamous and Salmon Arm famous for its fleet of houseboats. To the south of Shushwap Lake is the sunny and hot Okanagan Lake region. The only major city on the Trans-Canada Highway is Kamloops, where the North Thompson River joins the South Thompson.
From here, you can catch the ferry across the Georgia Straight to Nanaimo, on Vancouver Island. The ferry ride is typically 90 minutes. From there it's a two-hour drive south through towns like Cowichan, Duncan and Mill Bay to Victoria and "Mile 0" of the Trans-Canada Highway.