You can't.
Code running in a web page does not have access to the user's file system. You can only access files which the user explicitly gives you access to, either by selecting them in an
<input type="file">
, or by dragging them into your page.
Using files from web applications - Web APIs | MDN[
^]
And no, before you ask, there is no way around that. If there was, it would be a major security vulnerability.