Audiobookshelf or booksonic to host the media. As mentioned, populate it with content from your library

You are a fooking king, mate. By the gods this is a gift I will give again and again. Thank you

My family and I have saught certifications and pirated content has helped us pass without expense beyond the test. I find the content on udemy, pluralsight, et al is more relevant than youtube to teating for certificates.

If it is a general topic youtube or khan academy is pretty good, but deeper level skills are typically pay to learn unfortunately.

Trash guides keep scurvy from taking hold. An absolute must for any ship worth its salt