Run these commands (as SU) to update all dependencies and then reboot:

apt update
apt upgrade
apt autoremove
apt autoclean

reboot

install these packages:

apt install -y curl wget apt-transport-https git

create user for your project:

adduser APP_USER

run these commands to install nodejs:

cd ~
curl -sL https://deb.nodesource.com/setup_14.x -o nodesource_setup.sh
bash nodesource_setup.sh

apt install nodejs

rm nodesource_setup.sh

run this command:

apt install nginx

run this commands to add MySQL Repo:

wget http:https://repo.mysql.com/mysql-apt-config_0.8.14-1_all.deb

apt update

run this command to install MySQL:

apt install -y mysql-server

after that, run this command to configure it:

mysql_secure_installation

run this command to install MongoDB:

wget -qO - https://www.mongodb.org/static/pgp/server-4.4.asc | sudo apt-key add -
echo "deb http:https://repo.mongodb.org/apt/debian buster/mongodb-org/4.4 main" | sudo tee /etc/apt/sources.list.d/mongodb-org-4.4.list

apt update

apt install mongodb-org

run this command to set password for root:

mongo admin --eval 'db.createUser({ user:"root", pwd:"YOUR_PASSWORD", roles:[{role:"root", db:"admin"}]})'

after that go to this file:

nano /etc/mongodb.conf

and set auth to true:

auth=true

finally restart mongodb service

systemctl restart mongodb

run this command:

apt install redis-server

to set password for redis, go to this file:

nano /etc/redis/redis.conf

uncomment requirepass and fill it with your password:

requirepass YOU_PASSWORD

run this command to install PM2:

npm install -g pm2

run this command to install yarn:

npm install -g yarn

remember you have to create a MySQL database for your project (with superuser).

run this command with SU:

mysql

and run these commands to create a database and a user for it:

CREATE DATABASE YOUR_DB_NAME COLLATE utf8_general_ci;
CREATE USER 'YOUR_DB_USERNAME'@'localhost' IDENTIFIED BY 'YOUR_DB_PASSWORD';
GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, INDEX, ALTER, CREATE TEMPORARY TABLES, SHOW VIEW ON YOUR_DB_NAME.* TO 'YOUR_DB_USERNAME'@'localhost';
FLUSH PRIVILEGES;

if you want to proxy-forward your app with Nginx, copy these command in /etc/nginx/sites-available/default:

server {
  listen 80;

  server_name myapp.com;

  location / {
      proxy_pass http:https://localhost:3000;
      proxy_http_version 1.1;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection 'upgrade';
      proxy_set_header Host $host;
      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header X-Forwarded-Proto $scheme;
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_cache_bypass $http_upgrade;
  }
}

1- install nginx-extras:

apt install nginx-extras

2- open /etc/nginx/nginx.conf and turn off server_tokens :

http {
    more_set_headers "Server: Your_New_Server_Name";
    server_tokens off; 
}

3- restart nginx:

systemctl restart nginx

login with your project user.

first of all upload your files (or pull from git):

git pull YOUR_REPOSITORY_ADDRESS

then install packages with your package manager (npm or yarn):

npm install
yarn install

set your ENVIROMENT variables (mostly in .env file):

nano .env

run your app with PM2:

pm2 start app.js --name your_app_name