Docker use Multiple nginx server with single php instance - php

Question

I have several websites using php, each website is on a different docker.
In normal case, out of docker, all the websites use the same php installation.
How can that be achieved with docker?
this is my current setup. my single nginx docker uses this docker instance. (php-fpm.dockerfile only installing php-mysql).
php:
env_file: ".env"
build :
context : .
dockerfile : php-fpm.dockerfile
volumes:
- "./server/www/:/var/www/:cached"
I want to add another nginx server using this php instance, is it possible?
this is my entire relevant yml file, nginx_server instance us using php, how can i tell the php instance to process nginx_site instance as well.
version: "3.5"
nginx_server:
image: nginx
env_file: ".env"
links:
- php
- mysql
ports:
- "8081:80"
restart:
always
volumes :
- "./server/nginx/default.conf.php.template:/etc/nginx/conf.d/default.conf.template"
- "./server/logs/:/var/log/nginx/:cached"
- "./server/www/:/var/www/:cached"
command : /bin/bash -c "envsubst '$$NGINX_HOST,$$NGINX_ROOT,$$NGINX_INDEX_FILE,$$NGINX_PORT' < /etc/nginx/conf.d/default.conf.template > /etc/nginx/conf.d/default.conf && nginx -g 'daemon off;'"
environment:
- NGINX_HOST=$NGINX_SERVER_HOST
- NGINX_ROOT=$NGINX_SERVER_ROOT/public
- NGINX_INDEX_FILE=index.php
- NGINX_PORT=8081
nginx_site:
image: nginx
env_file: ".env"
links:
- php
- mysql
ports:
- "8082:80"
restart:
always
volumes :
- "./site/nginx/default.conf.php.template:/etc/nginx/conf.d/default.conf.template"
- "./site/logs/:/var/log/nginx/:cached"
- "./site/www/:/var/www/:cached"
command : /bin/bash -c "envsubst '$$NGINX_HOST,$$NGINX_ROOT,$$NGINX_INDEX_FILE,$$NGINX_PORT' < /etc/nginx/conf.d/default.conf.template > /etc/nginx/conf.d/default.conf && nginx -g 'daemon off;'"
environment:
- NGINX_HOST=$NGINX_SITE_HOST
- NGINX_ROOT=/var/www/
- NGINX_INDEX_FILE=index.php
- NGINX_PORT=8082
php:
env_file: ".env"
build :
context : .
dockerfile : php-fpm.dockerfile
volumes:
- "./server/www/:/var/www/:cached"
thanks