Laravel how to use DB class in model?

Question

Laravel

I created a model using php artisan make:model "Name" and created a function there that uses the DB class to work with the database, and I accessed the model of this function from the controller, but the error "Class 'App \ DB' not found" came out.
Model code:

<?php

namespace App;
use Illuminate\Database\Eloquent\Model;

class Hello extends Model
{
    public function showName($id){
      $users = DB::select('select name from users where id=?', [$id]);
      return $users;
    }
}

Controller code that uses this model:

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App;
class HelloController extends Controller
{
  public function show($id){
  $usersObj = new App\Hello();
  $users = $usersObj->showName($id);
  return view('hello', compact('users'));
  }
}

Answer 1

What the hell is this anyway? What the hell do you need a Hello model for?
Why can't you just get the user from his model?

public function show($id){
  $userObj = User::find($id);
  $userName = $userObj->name;
  return view('hello', compact('userName'));
  }