Content from youtube

May I use videos on youtube as content for making lessons? I want transcribe them and then read out loud what I have written. Next question. May I use articles from

You can use content from YouTube and from Wikipedia: there is no problem if you don’t make it public.

My gut feeling says that, if you are going to upload transcribed YouTube videos for public use, you’d need to have the permission of the YouTuber. As for Wikipedia, it is a encyclopedia meant for public use but I think you’d still have to have permission.

Yes, and make sure you watch this Import Any YouTube Video into LingQ - YouTube