Only if you apply to become a Canadian citizen. Once you get residency in Canada you can apply for provincial healthcare.
One way is to sign a form confirming that you want your child to be a Canadian citizen, then when the papers are signed, they're a Canadian citizen.
can a Canadian citizen become us citizen
No, you would have to either have dual citizenship or become only a Canadian citizen
No, they do not become a citizen by virtue of marriage.
I can state definitely that Americans can become Canadian citizens; I myself was an American, born in New York, and I am now a Canadian citizen. This does not, of course, mean that every American can become a Canadian citizen. Canada, like any other country, has specific citizenship requirements, and immigration requirements. Not everybody qualifies. But some do.
There is no such thing as a citizen of England in international law. People of England, Scotland, Wales and Northern Ireland are all British citizens in international law. Canada is an independent country and anyone who wanted to become a Canadian citizen would have to apply to the Canadian authorities in the same way that a Canadian would have to apply to the British authorities if they wanted to become a British citizen.
the simplest way is to marry a canadian citizen
You can become a citizen just like any other immigrant. Having family who are US citizens might make it easier, though.
You can lose it if you become a Canadian citizen through Naturalization.