I’ve always been a very reluctant affiliate marketer. My business model has always been selling online courses.
And as a course creator yourself, I don’t advise you pour your precious time and energy into building other people’s businesses for tiny percentages when you could be building your own.
However, there's nothing wrong in allowing your audience to reward you a little for recommending stuff they might find useful.
So I occasionally use affiliate links. They're links that if you click and later go on to buy that product, I get a little commission payment. You don't pay any more than you would have anyway.
One: I’m strictly only ever an affiliate for stuff I personally own and love and use regularly.
Two: I'll always do my best to flag up the fact that a link is an affiliate link. I don't know what the law is, quite frankly, but I do always try and do the right thing.