How to print anything in a twig template file
better practice is to do that in preprocess functions !


so, fe. in preprocess page, you can access the node (if existing) via the $variables array and so on ..., then you add your own variables for the twig template, like:

$variables['my_fancy_block'] = \Drupal::service('renderer')-&gt;renderRoot($whatever);


and access this like:

{{ my_fancy_block }}