Your data will be returned as an array of entities:
Your "getUsers()" method might look like this:
/**
* Returns an array of User entities.
*/
public function getUsers()
{
return $this->em->getRepository('My\Entity\User')->findAll();
}
The method returns an array of objects (specifically, objects of class \My\Entity\User).
In your view script, you might do something like:
<h1>All Users</h1>
<?php foreach($users as $u): ?>
<?= $u->getUsername(); ?><br/>
<?php endforeach; ?>
So, when you ask about "go about using entites to grab information from the DB...", what you really want to do is "use the EntityManager (and/or EntityRepositories) to grab entities from the DB".
Remember: Entities themselves don't know about persistence (the DB). But the EntityManager and Repositories do.
Finally, based on this question, and another of yours I answered, I suggest you take a look at Repositories in Doctrine. You seem to be reinventing that wheel to some degree.