The best way to learn more about LearnDash is to go through their documentation. You can access all of their documentation from here: LearnDash Documentation

Documentation categories:

Getting Started (Overview & Installation)

LearnDash Core (Learn how to build courses, lessons, topics, quizzes, etc)

Add-Ons (LearnDash supported plugins and third-party plugins)

Users & Groups (User management, creating and managing LearnDash groups)

Reporting (User data, quiz stats, ProPanel, etc)

User Guides (Detailed instructions on how to use popular LearnDash features)

Troubleshooting (Identify & fix LearnDash-related issues)

FAQs (The most commonly asked questions from our users)

Account & Billing (Your account, license & billing information)