SSH Commands

• adduser #username
• usermod -aG sudo #username
• sudo su
• nano #file name
• sudo ufw allow ssh
• sudo ufw enable
• pwd: how current directory (full path to where you are right now).
• ls: show directory contents (list the names of files).
• ls -a all files
• ls -h contents
• ls -r sub-directory
• ls -is size
• ls -alh all folders with detail
• cd: change directory
• cd.. move up one directory
• cd / go to root
• cd - previous directory
• mkdir
• touch: create a new file.
• rm: remove a file
• cat: show contents of a file.
• pwd: show current directory (full path to where you are right now).
• cp: copy file/folder
• mv: move file/folder
• grep: search for a specific phrase in file/lines.
• find: search files and directories.
• vi/nano: text editors.
• history: show last 50 used commands.
• clear: clear the terminal screen.
• tar: create & unpack compressed archives.
• wget: download files from the internet.
• du: get file size.
• chmod
• free -mcg
• whoami
• netstat
• top: memory, cpu, 
• df -h: disk usage

Nano editor commands

• Find: Ctrl+W
• Exit: Ctrl+X
• Save: Crtl+O
• Cancel: Ctrl+C

In nano's help texts the Ctrl is represented by a caret (^), so Ctrl + W is shown as ^W, and so on. The Alt key is represented by an M (from "Meta"), so Alt + W is shown as M-W.