Getting the workflow associated to a node type
Workflows are configuration entities so you can load them using their id:

$workflow = $this-&gt;entityTypeManager-&gt;getStorage('workflow')-&gt;load('workflow_machine_name');


Or "query" them using the Entity Query (check the Drupal 8 example shown here):

$query = $this-&gt;entityTypeManager-&gt;getStorage('workflow')-&gt;getQuery();
$query-&gt;condition('type_settings.entity_types.node', 'article', 'IN');
$workflows = $query-&gt;execute();


The condition is a proof-of-concept drawn from another config entity query but is the right path you need to test it agains the workflow entity schema.