Canada has three levels of 'regulators'. As stated, the Paramedic Association of Canada developed the National Occupational Competency Profiles (NOCPs) for EMRs, PCPs, ACPs, and CCPs. This is only a recommended framework. Each province has a regulator. Alberta and Saskatchewan have independent College of Paramedics' ($$$) and the other provinces have a division within the government, usually the Ministry of Health (typically free). The provinces outline the scope of practice and for the most part reflect the NOCPs but there is significant provincial variation. Lastly there is the individual employer. Their medical director may choose to allow the paramedics to work to the full provincial scope or limit it but not exceed it.
Now here's the proverbial wrench. The three Canadian territories (Yukon, Northwest Territories, and Nunavut) are federal and therefore do not have a regulator. However, it's been my experience that most employers in these regions require registration in one of the provinces, typically Alberta.
Re: the Agreement of Internaitonal Trade (AIT) and Labour Mobility. Speaking from experience, it can be easy or an absolute nightmare depending which province you're moving from/to. I don't know the exact US to Canada process, but I know some provinces will do a Scope of Practice review. I've seen fees in the area of $500 for this.
Your best bet would be to start with the potential employer and work back from there.
Note: For reference, a PCP is equvilant to an EMT-Advanced.
Re: flight certifications, to the best of my knowledge the only province that deliniates their paramedic scopes to indicate 'flight' is Ontario.
Another point of consideration is that there are bridging pathways if you have a Bachelor's degree as a Registered Nurse (RN). They consider this equvilant to a Critical Care Paramedic (CCP) but I do not know what additional testing/training may or may not be required.
