Initial setup for ubuntu

Setup Your Server Name

to see detail your server using command

hostnamectl

to change your server name using command

hostname <yournewname>

Add User to Server

add new user

adduser <newuser>

add sudo command to user using command

usermod -aG sudo <newuser> 

set password for user

passwd <newuser>

see detail user in ubuntu system in /etc/passwd

disable root remote login in /etc/ssh/sshd_config

PermitRootLogin no

if you login to newuser use this command to get root permission

sudo su -