Please try to describe your issue in more detail in the ‘tell us what is happening’ section in future, you can write your own text in this section. It makes helping much easier.
You need to write the doctype declaration exactly as the lesson gives it. Does your code match the lesson code?
<!DOCTYPE html>
<DOCTYPE html
Also, the lessons previously covered how to writes html element and how to add attributes and values to them. You need to use the same formatting for the html element.