Cybersecurity is a very broad field. "learn cybersecurity" is a bit like "learn medicine". You should learn the broadest possible IT basics, especially those related to data transmission and storage (networks, communication protocols, data carriers, backup systems, encryption). After that, you will probably be faced with choosing a specific specialization.
One great resource for learning about cybersecurity is the Cisco Networking Academy. They offer a free, self-paced course called "Introduction to Cybersecurity" that will teach you the basics of cybersecurity. You can find the course at this link: https://skillsforall.com/course/introduction-to-cybersecurity
Once you've completed the introductory course, you can continue your education with Cisco's other cybersecurity courses. They offer a variety of courses at different levels, so you can find one that's right for your skill level.