Save data with a resource model in Magento

We already have our PostFactory and Post classes injected into PostRepository within its constructor:

<?php

declare(strict_types=1);

namespace Macademy\Blog\Model;

use Macademy\Blog\Api\Data\PostInterface;
use Macademy\Blog\Model\ResourceModel\Post;
use Macademy\Blog\Api\PostRepositoryInterface;
use Magento\Framework\Exception\NoSuchEntityException;

class PostRepository implements PostRepositoryInterface
{
    public function __construct(
        private PostFactory $postFactory,
        private Post $postReso...