test/app/Http/Models/TemplateLibrary.php

<?php

namespace App\Http\Models;

use Illuminate\Database\Eloquent\Model;

class TemplateLibrary extends Model
{
    protected $primaryKey = 'id';
    protected $table = 'template_library';

    public function templateLibraryRelation()
    {
        return $this->hasMany(TemplateLibraryRelation::class, 'template_library_id', 'id');
    }
}