How did you research this question?
Why I ask is that I'm encountering folk that get upset at using google or taking classes on programming and web creation classes.
A few more think or write "just tell me what I need to know." These folk think that a subject could be covered in one paragraph. Which is true if you tell them google it. They usually melt down to reply it as unhelpful.
So let's hear from you what research you are doing as well as if you were in a school that forbade use of google and wikipedia.
If you are too lazy to do a simple google on the subject then I suspect you are too lazy to put in the effort to learn it.
I agree completely with the other two replies that you do have to put the work in.
It's very easy to find how to create your first html file on internet. I suspect that many people give up at this point because they see they've only learned how to display "Hello World".
The following may not be obvious if you're really starting from zero:
Paste the "Hello World" or whatever into a text file on your computer and (assuming Windows) save it under "all files" with its name followed by the extension .html, not .txt. Then mess around with it as much as you like, adding other stuff that you've read about. See what it looks like in your browser. Make other files, then, quite a bit later, google "learn css" and "free html editor".