SHELL

add user to sudoers

usermod -aG sudo username

add sudo user ubuntu

# add a user and set a password
adduser USERNAME

# add user to sudoers / sudo groupe with command below
usermod -aG sudo USERNAME

add user to sudoer

sudo grep -B1 -i '^%sudo' /etc/sudoers

# Allow members of group sudo to execute any command
#%sudo	ALL=(ALL:ALL) ALL

sudo adduser <UserNameHere> sudo

or

sudo usermod -aG sudo <UserNAmeHere>

id  <UserNAmeHere>

add sudo user ubuntu 18

sudo usermod -aG sudo [username]