When I launch the html page created with vim the browser doesn’t show me the web page but the code

I started to approach Linux recently and i started discovering the text editor vim, but starting to write my first html code I have the first problem, I wrote a simple html code and when I launch it on Firefox doesn’t show me the web page but the code. I think the problem is Vim because it’s like that doesn’t recognise characters such as comments(#) ecc.