blog/app/Models/Tag.php

<?php

namespace App\Models;

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

class Tag extends Model
{
    use HasFactory;

    protected $fillable = [
        'name'
    ];

    public function blogPosts(): BelongsToMany
    {
       return $this->belongsToMany(BlogPost::class);
    }

}