How to reverse-combine docker nginx-proxy with non-docker ported sites?

Question

Nginx

Decided to crawl all the same on the Docker.
Of course, I still do not fully understand all the charms of it.
Therefore, my question may be solved tritely.
In general, the server has a bunch of sites on nginx+php, nginx+pm2+nodejs.
I hang nginx-proxy on port 80 of the server.
I understand what to do with sites migrated to docker.
But what to do with non-migrants?
How, for now, with little bloodshed, can they also be sent (made available) to nginx-proxy?

Answer 1

Forward the ports on which the rest of the sites rise.