Google's SEO Starter Guide: This is a comprehensive resource provided directly by Google that covers the fundamentals of SEO. It's a great place to start and it's free.
Moz's SEO Learning Center: Moz is a well-respected authority in the SEO field. Their SEO Learning Center offers a variety of resources, including guides, videos, and quizzes, all aimed at helping you learn SEO for free.
HubSpot Academy's SEO Training Course: HubSpot offers a free SEO training course that covers everything from keyword strategy to on-page SEO tactics. It's a great resource for beginners looking to learn SEO.
SEMrush Academy: SEMrush is a popular SEO tool, and they offer free courses through their SEMrush Academy. These courses cover a wide range of topics related to SEO and digital marketing.
Coursera's SEO Specialization by UC Davis: Coursera offers a specialization in SEO created by the University of California, Davis. While the specialization itself isn't entirely free, you can audit the courses for free to access the content.
YouTube Channels: There are many YouTube channels dedicated to SEO tutorials and tips. Some popular ones include Backlinko, Neil Patel, and Ahrefs. While not structured like a traditional course, you can find a wealth of information by watching their videos.
Remember, while these courses are free, investing time and effort into learning and practicing SEO is crucial for becoming proficient. Additionally, consider supplementing your learning with real-world projects and staying updated with industry news and trends.