The forum has areas that permit commercial postings. The ability to educate in non-commercial areas depends on how you define free. For example, these sort of items don't qualify...
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On the other hand, if you really do just want to completely freely share and educate people about how you trade, that opens a lot more folders up to you. Before starting, you may want to check the review page for the broker you'll be sharing info from. If it's labelled as a scam, has major warnings on the page, or has a really low rating, that will discourage some people from following you.
You can PM me if you have any more questions. I don't always have time to answer quickly, but usually can get back to people in a few days.