Subdomain on another server?

Question

Nginx

Hello! Strongly do not kick, I'm new to this business. The bottom line is this, there is a
working site - site1 on one server 1.22. The site is up on nginx.
and site2 on - 1.23
all servers are local, only 1.22 looks in the Internet, and 1.23 is visible only within the network.
Question.
How can I make it so that people who came to site1 and clicked on the link could go to site2. I think you need to climb in the nginx settings, just tell me what and how to set it up.
I would be grateful for examples.

Answer 1

if possible an example of some kind of config for an example.