Usually online, if it's too good to be true then alarm bells should be ringing. There's plenty of great info on structuring content and writing available without having to sign up to a course. My guess would be that maybe not a scam, but you would get some perfunctory boilerplate instructions, and because they've got your email, lots of spam.
They may also try to upsell you other products and services. It would be good to check reviews of the aforementioned courses, but most reviews for online reports and stuff are spam anyway... You can't win, but personally I would spend time looking for paid stuff that has testimonials and stuff rather than free - you usually get what you pay for.