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Hi I have been looking for a week, I searched throughout the web but didn't get information. So, I am here to get some guidance. My question is that are there any courses, techniques, or paid communities available where I can learn advanced puro blackhat SEO or advanced greyhat SEO? Please...

Is it illegal to create a reaction video to someone's paid course on YouTube? Will I face any legal issues or potential consequences if I do so? I want to ensure that I'm respecting copyright laws and avoiding any infringement on intellectual property rights.