Where is the code for join the Html to the Css archive?

Answer 1

What do you want to do? Your issue is not clearly defined. Your tags ask something for a border and a join and your question itself could be interpreted as import of HTML file into CSS which would be totally wrong.

If you want to import an CSS file into an HTML file, look it up here:
https://www.w3schools.com/css/css_howto.asp

Please be more accurate in your question's description next time.

Answer 2

CSS is not stored in an archive but a file.

CSS is linked into a HTML file not the other way around.

What is ment by where is the code? Are you asking for an example?