investbrain/app/Http/Controllers/HoldingController.php

<?php

namespace App\Http\Controllers;

use App\Models\Holding;
use App\Models\Portfolio;
use Illuminate\Http\Request;

class HoldingController extends Controller
{

    /**
     * Display the specified resource.
     */
    public function show(Request $request, Portfolio $portfolio, String $symbol)
    {

        $holding = Holding::with(['market_data'])
                            ->symbol($symbol)
                            ->portfolio($portfolio->id)
                            ->firstOrFail();

        $transactions = $holding->transactions;
                        
        return view('holding.show', compact(['portfolio', 'holding', 'transactions']));
    }
}