How to update a PDF file in post

I have made a post, in which I have title, content, image and category , all is working fine. I want to add a section of PDF file to post.

I want to upload a pdf file, For image I have made already

it's web.php \

Route::post('/post/store', [ 'uses' => 'PostController@store', 'as' => 'post.store' ]);

Controller public function store(Request $request) {

    $this->validate($request, [


       'title' =>'required',

        'featured'=>'required|image',

        'content'=>'required',

        'category_id'=>'required'

    ]);

    $featured= $request->featured;

    $featured_new_name=time().$featured->getClientOriginalName();

    $featured->move('uploads/posts', $featured_new_name);

    $post = Post::create([

        'title'=>$request->title,

        'content'=>$request->content,

        'featured'=>'uploads/posts/'. $featured_new_name,

        'category_id'=>$request->category_id,

        'slug'=>str_slug($request->title)


    ]);


  Session::flash('success', 'New Blog has been Published on Website for 

  Particular Menu');

  return redirect()->back();

}

    post.blade.php

    @extends ('layouts.app')

   @section('content')

@if(count($errors)>0)

    <ul class="list-group">

        @foreach($errors->all() as $error)

            <li class="list-group-item text-danger">

                

            </li>

        @endforeach

    </ul>

@endif

<div class="panel panel-default" >

    <div class="panel-heading">

        <div class="text-center">

       <b> Create a new Blog</b>

        </div>

         </div><BR>

         <div class="panel-body">

        <form action="" method="post" 

                 enctype="multipart/form-data">

            

              <div class="form-group">

                <label for ="title">Title</label>

                <input type="text" name="title" class="form-control text-danger">
            </div>


            <div class="form-group">
              <label for ="featured">Image/Featured</label> <input type="file" name="featured" class="form-control">
            </div>

            <div class="form-group table-dark">
                <label for ="category">Select a Menu</label>
                <select name="category_id" id="category" class="form-control" >
                     @foreach($categories as $category)
                        <option value=""></option>
                     @endforeach
                </select>
            </div>

            <div class="form-group">
               <label for ="content">Content</label>
               <textarea name="content" id="content" cols="5" rows="5" class="form-control"> </textarea>
            </div>

    <div class="form-group">
        <div class="text-center">

            <button class="btn btn-success" type="submit"> Submit Blog</button>
        </div>
   </div>

        </form>   </form>

</div>
</div>

@stop

@section('styles')

<link href="http://cdnjs.cloudflare.com/ajax/libs/summernote/0.8.11/summernote.css" rel="stylesheet">

@stop

@section('scripts')

<script src="http://cdnjs.cloudflare.com/ajax/libs/summernote/0.8.11/summernote.js"></script>


<script>
    $(document).ready(function() {
        $('#content').summernote();
    });

</script>

@stop

via Chebli Mohamed