bash: shutdown: command not found

I installed the latest version of Debian (netinstall).
I have the problem, that the terminal does not know commands like

,

, and so on.
When I do

shutdown

it tells me it is in

/usr/sbin

.

I fixed this on a different installation try by writing /usr/sbin into /etc/profile where the $PATH is written.
But this time it did not work.

I looked at this: https://wiki.debian.org/EnvironmentVariables , but either those files did not exist or I did not know where to put the path.
And doing export PATH=$PATH:usr/sbin is not permanent, it's gone after reboot, so that is garbage as well.

Edit: Wait, maybe I have to change the PATH in /etc/environment?!
I have to test this once I give Debian another try.