Create new sudo user; disable root login via SSH

noroot-ssh.txt

# create a new non-root user
adduser <new-username>
# follow prompts

# give sudo permissions to the new user
usermod -aG sudo <new-username>

# check groups for new user
groups <new-username>

# edit sshd_config settings
vim /etc/ssh/sshd_config

# change `PermitRootLogin` from yes to no

# Authentication:
#LoginGraceTime 2m
PermitRootLogin no
#StrictModes yes
#MaxAuthTries 6
#MaxSessions 10

# save the changes

# restart the ssh daemon

systemctl restart sshd

# check the status of sshd

systemctl status sshd 

# test from another terminal:
# try logging in as the new user and then becoming root with:
sudo su -

# if the above works, try logging in as root again over SSH
# expect this to fail
# if you enter the correct password, you should still get an 'access denied' error message