Which colonies joined the federation?

The first 4 were Ontario, Quebec, Nova Scotia and New Brunswick.

Canada purchased Ruperts Land and Northwest Territories. From that land they created Manitoba. They were not a colony before joining.

British Columbia was a colony, they joined next.

PEI was also a colony.

The Yukon, Saskatchewan, and Alberta were not British colonies unlike Newfoundland.

Nunavat was not a colony other than a Canadian colony.

So the answer is Ontario, Quebec, Nova Scotia, New Brunswick, British Columbia, PEI and Newfoundland.