Drupal 8: How to retrieve field values when i use loadMultiple to load multiple node ids
You should do like

$node_storage = \Drupal::entityTypeManager()-&gt;getStorage('node')-&gt;loadMultiple($nids);
foreach ($node_storage as $node){
   $field_merchant_id = $node-&gt;get('field_merchant_id')-&gt;value;
}


Here you are using "user" which should be replaced by "node" to access node values.
And also to access "field_merchant_id", you need to get that from $node.