simples-painel/app/Models/Grupos.php

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsToMany;

class Grupos extends Model
{
    use HasFactory;

    protected $table = "grupo";
    protected $fillable = [
        'name',
        'id_empresa',
        'system',
        'status'
    ];
    
    public function users(): BelongsToMany
    {
        return $this->belongsToMany(User::class, 'grupo_usuario','id_usuario', 'id_grupo')->first();
    }

    
}