Configure nextcloud-fpm docker-compose with bare metal nginx

I'm trying to install Nextcloud on my server. The nginx service is installed directly on bare metal (Ubuntu)

I starting from the docker-compose found at https://github.com/nextcloud/docker/tree/master/.examples/docker-compose/with-nginx-proxy/postgres/fpm

version: '3.8'

services:
  postgres-nextcloud:
    image: postgres:alpine
    restart: always
    ports:
      - 5435:5432
    volumes:
      - postgres-nextcloud-data:/var/lib/postgresql/data
    env_file:
      - db.env

  redis-nextcloud:
    image: redis:alpine
    restart: always

  nextcloud:
    image: nextcloud:fpm-alpine
    restart: always
    ports:
      - 8083:9000
    volumes:
      - /var/www/cloud.domain.com:/var/www/html
    environment:
      - POSTGRES_HOST=postgres-nextcloud
      - REDIS_HOST=redis-nextcloud
      - POSTGRES_PORT=5432
    env_file:
      - db.env
    depends_on:
      - postgres-nextcloud
      - redis-nextcloud

  web:
    build: ./web
    restart: always
    volumes:
      - /var/www/cloud.domain.com:/var/www/html:ro
    environment:
      - VIRTUAL_HOST=cloud.domain.com
      - LETSENCRYPT_HOST=cloud.domain.com
      - LETSENCRYPT_EMAIL=dev@domain.com
    depends_on:
      - nextcloud
    networks:
      - proxy-tier
      - default

  cron:
    image: nextcloud:fpm-alpine
    restart: always
    volumes:
      - /var/www/cloud.domain.com:/var/www/html
    entrypoint: /cron.sh
    depends_on:
      - postgres-nextcloud
      - redis-nextcloud

But with my knowledge in web server I haven't found the way to properly configure my "local" nginx.

I've many other website, app already working using this nginx instance All the different config are in the sites-available directory The config for the Nextcloud project is named cloud.mydomain.com

with this nginx config I only get a File not found. Page

server {
  root /var/www/cloud.domain.com;
  server_name cloud.domain.com www.cloud.domain.com;

  index index.html index.htm index.php;

  charset utf-8;

  location / {
      try_files $uri $uri/ /index.php?$query_string;
      gzip_static on;
  }

  location = /favicon.ico { access_log off; log_not_found off; }
  location = /robots.txt  { access_log off; log_not_found off; }

  error_page 404 /index.php;

  location ~ \.php$ {
      try_files $uri =404;
      fastcgi_split_path_info ^(.+\.php)(/.+)$;
      fastcgi_pass localhost:8083;
      fastcgi_index index.php;
      include fastcgi_params;
      fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
      fastcgi_param PATH_INFO $fastcgi_path_info;
  }

  error_log  /var/log/nginx/error.log;
  access_log /var/log/nginx/access.log;

  listen [::]:443 ssl; # managed by Certbot
  listen 443 ssl; # managed by Certbot
  ssl_certificate /etc/letsencrypt/live/cloud.domain.com/fullchain.pem; # managed by Certbot
  ssl_certificate_key /etc/letsencrypt/live/cloud.domain.com/privkey.pem; # managed by Certbot
  include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
  ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot
}

server {
  if ($host = www.cloud.domain.com) {
      return 301 https://$host$request_uri;
  } # managed by Certbot


  if ($host = cloud.domain.com) {
      return 301 https://$host$request_uri;
  } # managed by Certbot

  server_name cloud.domain.com www.cloud.domain.com;

  listen 80;
  listen [::]:80;
  return 404; # managed by Certbot
}

I understand that -fpm app need a proxy but I don't really understand how to link it to my existing nginx set up. With the nginx NOT running in a docker container.

Thanks for your time!