There’s a boatload of resources to learn from, here are a few I’ve used or am familiar with:

Online, Video-based Training:

• https://itpro.tv/ – IT training geared towards earning certifications. About $570/year
• https://www.pluralsight.com/ – Technology, security, software development, and a lot more. $299/year.
• https://www.coursera.org/ – Sort of a big fat aggregation of online courses from universities and such. The Google IT Support Professional Certificate is fantastic. Price varies depending on the classes taken.

Professional, In-Person Training:

• https://www.sans.org/ – SANS is probably the best in-person training, but it is expensive; At leat $5,000 for a week-long class, but some on-demand online classes are less expensive. SEC401: Security Essentials is a great intro course.
• https://www.offensive-security.com/ – the makers of Kali Linux have a couple courses in penetration testing and a rigorous certification exam. Kali is free and the class costs about $1,000.