einundzwanzig-app/database/factories/ParticipantFactory.php

<?php

namespace Database\Factories;

use App\Models\Participant;
use Illuminate\Database\Eloquent\Factories\Factory;

/**
 * @extends Factory<Participant>
 */
class ParticipantFactory extends Factory
{
    protected $model = Participant::class;

    public function definition(): array
    {
        return [
            'first_name' => fake()->firstName(),
            'last_name' => fake()->lastName(),
        ];
    }
}