When you export an org file to html, a date will appear in the html source though commented.
Example, line 5 of https://imgur.com/a/BY4QSdt .
You need to set the appropriate export option, which is
timestamp. It's described at Export Settings, but I always find that section ridiculously confusing, so here are some examples:
Either globally using a variable:
(setq org-export-with-timestamps nil)
or globally using a keyword:
#+options: timestamp:nil * headline one two three
or on an individual headline:
* headline #+options: timestamp:nil one two three