Map a page to a subdomain in wordpress

I’m trying to map a specific page to a subdomain in wordpress.

For example, I have this wordpress page: www.mysite.com/mypage

I want that when someone enters mypage.mysite.com the content of www.mysite.com/mypage shows (not with a redirect).

Can’t find a way to do this.

I’ve already tried with Rewrite rules in .htaccess file with no luck.

I tried something like this:

RewriteCond %{HTTP_HOST} mypage.mysite.com
RewriteRule ^(.*)$ http://mysite.com/mypage$1 [R=301,L]

But this redirects instead of invisible showing the content of the page.

Is this possible to achieve with a subdomain?

I’ve tried some solutions I’ve found here with no luck.

Many thanks.