There are many learning resources on various websites. The more famous ones are:
3. Safe Cow Classroom
An online learning platform for practical network security skills created by Gu'an College, a first-class information security education and training institution in China. The platform provides value-added services for network security practitioners: helping practitioners and enthusiasts improve Kali Linux, malicious code analysis, mobile application security, Kerberos, machine learning and other practical network security skills; helping practitioners obtain CompTIA Security+, ISACA CISM, CSA CCSK, ITIL V4 and other primary security certifications.
In addition, Ping An Niu classroom has long practiced "network security public welfare - respecting teachers and valuing education": providing a large number of free online courses for teachers and students majoring in network security in colleges and universities to help them master the knowledge of network security, so that they can better understand and Know about cybersecurity.
5. SANS Cyber Aces
SANS is known for its eye-wateringly expensive courses, but also offers cybersecurity courses that teach the basics -- operating systems, networking, and system administration. These free trainings are great for familiarizing rank-and-file employees with security issues. Employees or job seekers who complete the course quickly can take it further in depth.
SANS Cyber Aces Online is an online course that teaches the core concepts of information security system assessment and protection. Developed by SANS, this course is the most credible and largest information security training and security certification in the world.
The bigger the cybersecurity job market, the more students are prepared to shell out money for SANS' well-crafted advanced courses. The free class is meant to lure potential students, but it can also benefit companies struggling to build a talent pipeline.
7. Offensive Security's Free Metasploit Course
Metasploit is an automated attack tool used by almost every cybersecurity professional today. Offensive Security is the producer of Kali Linux and OSCP certification. It offers a free Metasploit online course. The perfect starting point.
Its website reads: The platform uses a heuristic teaching method to systematically teach you how to use Metasploit. Plus, this free online ethical hacking course is a cheat sheet for penetration testers, red teams, and other security professionals.
In addition, there are many people sharing their network security experience on CSDN, such as my channel.