erruers

Run echo $PATH Does it contain /usr/local/sbin?

If not then add PATH=/usr/sbin/:$PATH to your .profile file.

Also, check that nginx is installed in /usr/local/sbin, by going into this directory.

If not then install it by using following commands:

sudo apt update
sudo apt install nginx


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# usermod -aG sudo johndoe

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As 'root' -> Edit /root/.bashrc

Add to the end of the file:

alias reboot='systemctl reboot'
alias poweroff='systemctl poweroff'