I have add the user ADMIN in file /etc/sudoers.tmp (SEE BELOW) BUT still when I connect to the ADMIN user looks like this: admin@mydomain:/$ and not user ROOT admin@mydomain:~# What do I solve this? I am grateful to those who help me. Thank you.

User privilege specification
root ALL=(ALL:ALL) ALL
*admin ALL=(ALL:ALL) ALL
*

Members of the admin group may gain root privileges
*%admin ALL=(ALL) ALL
*

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

Is this command? sudo chown -R 755 admin and sudo chmod - R 755 admin or sudo chmod 755 /var/www/admin or sudo chown 755 /var/www/admin