Linux command: adduser

Adding users to Linux
adding a user to the sistem:
sudo adduser <username> [<group>]

To add a super user to the sistem:

• sudo adduser <username> sudo

Another option is:
adduser USERNAME
usermod -a -G sudo USERNAME

usermod -a -G adm,cdrom,sudo,dip,plugdev,lpadmin,sambashare,libvirtd USERNAME

To verify the groups that a user is part of:
groups USERNAME