how to add to html.twig from a node twig file?
You're going about it the wrong way, you cannot affect other Twig template files, it needs to be done way before you get to Twig. Everything you want to can be done using the Metatag module:

Supports a large number of commonly used meta tags, including the page title, canonical URL, description, etc, and for Facebook's Open Graph, Twitter Cards and Dublin Core via included submodules (see full list)