I want to paginate my select query in laravel

I have a problem in a query when I use pagination with select in laravel but I found some laravel elequoent code but problem is that also not work ... anyone who can help me to solve this problem, Thanks

    public function categoryall($urlid){
    //old query
    // $procat = DB::select('select * from products where category_id in 
    // (select id from categories where parent_id = ?)', [$urlid]);

    // new
    $procat = Product::whereIn('category_id', function($query){
        $query->select('id')
        ->from(with(new Category)->getTable())
        ->where('parent_id', [$urlid]);
    })->paginate(5);

    return view('products.category')->with(compact('procat'));

  }

via Chebli Mohamed