I did my first lesson some time ago, it took a lot of time to get it published

Here's the result:
link to lesson
I think I've received some great feedback so far

I want to make my future lessons better, so my question is how do I include links and images into them or perhaps different colors?

without the dots

I know those codes for forums, do they work on those lessons as well? If not, which do?

Other advice on how to improve my lessons would be welcome as well (if you can bother to read the one I posted that is).^^

thanks in advance
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