Unable to fetch data from Laravel eloquent relationships array

Question

i've an array like below for $response . i wanted to fetch the user field alone & files field lying inside the user from it . i tried like $response['user'] & $response['user']['files'] , it shows the error undefined index . How can i achieve this?

[
    {
        "id": 14,
        "userId": 1,
        "courseDisplayName": "yuu",
        "aboutCourse": "kljkl",
        "user": {
            "id": 1,
            "name": "admin",
            "profilePicId": 93,
            "aboutUser": null,
            "files": {
                "id": 93,
                "FilePath": "contentq/contentqFiles/XwyC6JHK5T/Account.png"
            }
        },
        "files": null
    }
]

What am trying to do here is that ,the input couresId is array like [14,15] , So for each item in the array ,i wanted to fetch data from Course , user & files tables , for which the id of Course table has the value taken in input, userId of course table has the value of id in user table & fileId of course table has the value of id in files table. The realtions user & files are defined in the Course model.

$response=null;
foreach($request->courseId as $key => $row){
$response[] = Course::with([
        'user' => function($q)
         {
              $q->with('files:id,FilePath')->select('id', 'name' , 'profilePicId','aboutUser');
         },'files:id,FilePath']) 
            ->where('id',$row)
           ->get()
     ->makeHidden(['subjectId','skillId','courseUniqueName','active','created_at','updated_at','deleted_at','publish','course_patterns_id','paid_status','fileId','updatedBy']);
  }

**EDIT**

//$res=[];
 foreach($response as $row){
            
  $res['user'] = $row->user;  // error- Property [user] does not exist on this collection instance  
  $res['user'] = $row->first()->user;// works , but it will show only 1 set of data. i wanted all sets of data.   
} 

Answer 1

$response is an array or collection of array. you can't access $response['user'] without looping it. Either call $response->first() or make a foreach to loop through $response

Way One:

    $user = $response->first()->user;
    $files = $response->first()->files;

Way Two:

    foreach($response as $row){
        $user = $row->user;
        $files = $row->files;
       // use dd() these to see what you get
    }