I'm not a Canadian, but this is how I understand the situation. The provinces are saying that if their national government wishes to confiscate firearms, then the national government will have to supply both their own national police forces and use national monies to do so. The provinces are staying out of the entire affair.
Of course, the provincial authorities of Canada are NOT saying that they will actively prevent the confiscations.
We'll have to watch and see if Trudeau has another one of his adolescent tantrums about the provinces not kneeling before his royal wishes.
In Virginia, when the state legislators and former governor (current governor is conservative and would veto any such bill) were talking about banning semi-automatic rifles, over 90 county sheriffs (95ish, I think) said that they would not enforce any such law; PLUS, many of those sheriffs said that they would "deputize assault rifle owners", thus actively blocking the Virginia Commonwealth's actions. The state ("commonwealth", whichever nomenclature one prefers) would then have had to confiscate firearms from "county deputies" -- which would have been a MUCH larger issue. When Virginia's sheriffs stood up against Richmond, all of the liberal national news outlets went ballistic and made all manner of accusations along the line that the sheriffs were insurrectionists, enemies of civilized society, ... on and on. Me, I found it all quite delightful. I imagine that Thomas Jefferson and George Mason had a good laugh viewing all this from the spirit realm.
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