Before 1931, the so-called Imperial Parliament had the power to legislate for Canada, and any legislation they passed had supremacy over colonial legislation under the Colonial Laws Validity Act, 1865.

Between 1931 and 1982, the UK Parliament had the power to legislate for Canada only with the request and consent of the Canadian government. This arrangement was codified in the Statute of Westminster 1931.

In 1982, on the request and consent of the Canadian government, the UK Parliament removed its own power to legislate for Canada by passing the Canada Act 1982 (UK), which enacted the Constitution Act, 1982.

Canada remains a constitutional monarchy. The monarch of Canada is constitutionally required to be the same physical person as the monarch of the United Kingdom, but they are distinct legal persons (as is the monarch of each province).

It means they had a more significant ceremonial role. They've been uninvolved in Canadian government, laws, and policy for a long time. Arguably since the end of the great war

To add to the previous answer, we are technically still under the queen's authority so you could say that we are a constitutional monarchy, but it's all symbolic. Anything else would create public outcry. I personally think we should move out of this system, but it is hard to change a constitution specially since one of them still has not signed it...