getting product id in laravel

hi i'm trying to get the product id from table products to insert it into the wishlist table and this is how the controller is :

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;

use App\Http\Requests;
use App\Http\Controllers\Controller;
use Auth;
use App\User;
use App\Product;
use DB;

class listController extends Controller
{
    //
    public function getCreate(){

        $list=DB::table('wishlist')->get(['id','product_id']);
        $product=Product::get(['name','id','salary','image_name']);
        $user=Auth::user()->id;
        return view('contents.wishlist')->with('list',$list)
                                        ->with('product',$product)
                                        ->with('user',$user);
    }
    public function postCreate(Request $request){
        $id=$request->input('id');
        $user_id=Auth::user()->id;
        $product_id=Product::find('id');

        DB::table('wishlist')->insert(['id'=>$id,'user_id'=>$user_id,'product_id'=>$product_id]);
        return redirect()->action('listController@postCreate');
    }
}

what is the function i could use to get ?

via Chebli Mohamed