In Drupal 8 can a developer inject Full HTML Pages? I have done a lot of work in WordPress but want to develop a new site in Drupal 8. I have two specific questions before I start on my site.


Is it possible to inject full HTML pages via PHP into a Drupal 8 environment? I have full HTML content being served from an API for SEO purposes.


If the answer to #1 is NO:


Is it possible to change header and footer based on specific paths? So everything at /articles will get a certain header or footer? In this case I would want to pass an incomplete  tag and have the API call close the head tag and provide the body.
Usually you will not inject full HTML pages to Drupal, more likely you will inject your content as node-content. Then use a convenient theme for your needs.

Drupal has - like wordpress - themes. These are nested pieces of HTML code with TWIG syntax for dynamic content.

Unlike, wordpress, you can specify different themes for different URI paths (look for keyword theme_negotiator). I.e., you may configure to use an "article-theme" on path /articles.

But this is only the beginning of a very long story...