Add bootstrap5 CSS and JS from Official Docs

snippet.blade.php

<div class="accordion" id="accordionExample">

    @foreach($alldata as $item)


    <div class="accordion-item">
        <h2 class="accordion-header" id="{{ 'heading' . $item->category_name }}">
            <button class="accordion-button" type="button" data-bs-toggle="collapse" data-bs-target="#{{'collapse' . $item->category_name }}" aria-expanded="true" aria-controls="{{'collapse' . $item->category_name }}">
                $item->category_name
            </button>
        </h2>

        <div id="{{'collapse' . $item->category_name }}" class="accordion-collapse collapse show" aria-labelledby="{{ 'heading' . $item->category_name }}" data-bs-parent="#accordionExample">
            <div class="accordion-body">
                <ul class="list-group list-group-flush">
                    @foreach($item->product[0] as $key)
                    <li class="list-group-item"> {{ $key->product_name }} </li>
                    @endforeach
                </ul>
            </div>
        </div>

    </div>

    @endforeach

</div>

Please add the following CSS and JS CDN on file.