drupal_yp_install_profile/yp_install_profile.install

<?php
/**
 * @file
 * Install, update and uninstall functions for the yp_install_profile install profile.
 */

use \Drupal\node\Entity\Node;

/**
 * Implements hook_install().
 *
 * Perform actions to set up the site for this profile.
 *
 * @see system_install()
 */
function yp_install_profile_install() {
  // Can add code in here to make nodes, terms, etc.

  // Create homepage node.
  $node = Node::create([
    'type' => 'homepage',
    'title' => 'Homepage',
  ]);
  $node->save();
}