Converting multiple same name into one single name and also values get sum in laravel

I am trying to fetch the multi same name to single name also sum associated QTY values also.Show PART-ID as it's

example

I want to show like this

my controller

    public function productserach()
{ 
    $searchitem = Item_list::get();
    return view('products.product-serach',compact('searchitem'));
}

via Chebli Mohamed