siopas-istw-website/app/Exports/WarehouseExport.php

<?php

namespace App\Exports;

use App\Models\m_warehouse;
use Maatwebsite\Excel\Concerns\WithHeadings;
use Maatwebsite\Excel\Concerns\FromCollection;

class WarehouseExport implements FromCollection, WithHeadings
{
    /**
     * @return \Illuminate\Support\Collection
     */
    public function collection()
    {
        $nomor = 1;
        // Ambil data dari model Peti
        $warehouses = m_warehouse::select(
            'id',
            'name',
            'description',
            'address',
        )->get();

        // Modifikasi data dan tambahkan nomor
        $data = $warehouses->map(function ($warehouse) use (&$nomor) {
            return [
                'No' => $nomor++,
                'Nama Gudang' => $warehouse->name,
                'Deskripsi' => $warehouse->description,
                'Alamat' => $warehouse->address,
            ];
        });

        return $data;
    }

    public function headings(): array
    {
        return [
            'No',
            'NAMA GUDANG',
            'DESKRIPSI',
            'ALAMAT',
        ];
    }
}