Ubuntu Tutorials

Here is a page full of tutorials for Ubuntu 18.04

LAMP Server

How to install Linux, Apache, MySQL,PHP (LAMP) stack on Ubuntu 18.04

UBUNTU Uncomplicated Firefall UFW
UFW Essential Common Firewall Rules and Commands
AWS LightSail Instance OS Upgrade Walkthrough
How to disable IPv6 on Ubuntu 18.04
How to Allow MySQL Remote Access
How to setup SWAPFILE on AWS instance
How To Set Up Apache Virtual Hosts on Ubuntu 18.04
Proxy Server | Squid

Sources:

Ubuntu Tutorials
Ubuntu Server
Ubuntu Server Docs