How to show another site on my site?

Question

PHP

The bottom line is that the user comes to my site, for example mysite1.ru, and sees mysite2.ru.
The point is that this should be done without frames and redirects. Second site on https

Answer 1

This is not done in javascript and not in php.
Nginx is installed and proxying of requests to mysite2.ru is configured.

Answer 2

The domain dns contains A record of the site that needs to be shown, in fact there is nothing complicated