Nginx on another server?

Need advice on nginx server for erpnext.

Currently using erpnext on my office server. The install was done using the script from the following site.

All working.

It installs a nginx web server on the same server as erpnext.

Does the nginx web server need to be on the same machine as erpnext server?

We have a nginx web server on another server. This nginx server is already facing the internet and other sites are on it. Can we use this nginx server instead of the nginx server with the erpnext? So there is only one nginx server to erpnext.

What is the best practice for the nginx server for production erpnext?