There are plenty of amazing online school and course management themes and plugins available for WordPress. Bookingo is also worth a look. It lets you create an unlimited number of courses and course groups. It is made to play well with WPBakery Page Builder. It integrates with WooCommerce, PayPal, and Stripe.
This plugin is responsive and ready for mobile devices. It lets you create courses with a student limit, custom duration/schedule, location, and trainer information. You can create your own pricing rules and create coupons to attract more customers. Bookingo supports E-mail, SMS, and Telegram notifications.
This plugin comes with a custom form field builder. It lets you easily add promotional images and videos for each course. QuanticaLabs is the developer behind this plugin.