sudo usermod -l newUsername oldUsername

sudo usermod -d /home/newHomeDir -m newUsername

sudo adduser temporary

sudo adduser temporary sudo

sudo deluser temporary
sudo rm -r /home/temporary

sudo passwd root

exit

usermod -l <newname> -d /home/<newname> -m <oldname>

groupmod -n <newgroup> <oldgroup>

passwd -l root

exit

mount -o remount,rw /

usermod -l <newname> -d /home/<newname> -m <oldname>

groupmod -n <newgroup> <oldgroup>

mount -o remount,rw /

usermod -l <newname> -d /home/<newname> -m <oldname>

sudo -- usermod -l <newname> -d /home/<newname> -m <oldname>

sudo --  groupmod -n <newgroup> <oldgroup>

sudo vim /etc/passwd

user:x:500:501:username:home/user:/bin/bash

newuser:x:500:501:username:home/user:/bin/bash