/var/www/html/back/app/Models/ArticleToGroup.php
<?php

declare(strict_types=1);

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Support\Carbon;

class ArticleToGroup extends Model
{
    protected $table = 'article_to_group';

    protected $fillable = [
        'article_id',
        'article_group_id',
    ];

    public function articleGroup(): BelongsTo
    {
        return $this->belongsTo(ArticleGroup::class);
    }

}