I suppose they would need provincial agreement, although if a province refuses, the Feds may be able to implement something still. “It depends”.
How does it "depend"? The feds can't implement a healthcare program on the provinces without their consent. What is this "something" you speak of?
What seems most likely is something like universal healthcare programs in the provinces, possibly with federal funding help via transfers. The feds have a useful role in bulk buying of meds and can set some standards like healthcare. Feds and provinces can certainly work together on some things but getting them all to agree and having a national program seems unlikely. Some if not many provinces might give up on some points in exchange for funding, but again not without provincial consent. And like usual, with Alberta who knows, they might tell the feds to get bent, while Atlantic Canada would probably take anything they could get.