Adding user to unix server

adduser.sh

useradd -m username
passwd userpassword

# OPEN sudo visudo
# ADD a group like below
## Allows people in group wheel to run all commands
# %wheel        ALL=(ALL)       ALL
  %somegroupname        ALL=(ALL)       ALL
# Save your changes and exit the editor. 

# Add the user you created to the wheel group using the usermod command
usermod -aG wheel USERNAME

# Test the addition of USERNAME to group by sudo'ing to user
su USERNAME -
# To verify the groups of username
groups
> USERNAME somegroupname