Just what I thought. Your problem is not related with what is called a "Lesson" activity in Moodle. I suggest you re-post to the General Problems forum.
But please to be more precise when you describe your problem in your next post there.
In your original post you said "I have uploaded all coursework in HTML format" but now you say that you "compose a webpage as HTML". These are two different ways of doing things, so it is confusing. It would really help if you could say exactly what you are doing.
All the best,