Good start

1

sudo apt install -y mc curl jq wget htop hwinfo nmap vim

Some commands

top - see running processes

df - check free disk space

baobab - free disk space

screen - multiple virtual consoles in one real [ref], need installation in ubuntu

mc - file manager

ccsm - disabling smooth fades and animations (speedup interface, especially useful in VirtualBox)

sudo apt-get install compizconfig-settings-manager

then

ccsm

Set up SFTP server

See also