$PATH does not include sbin.

[RyzenWarrior]

When running the command 'bash wireguard-install.sh'

I get this error: '$PATH does not include sbin. Try using "su -" instead of "su".'

Running on Debian 12

[Gedrean]

Sometimes when you are running with su on its own, rather than sudo, or su - to switch to root, your path does not import "sbin" directories. This is why. Those sbin directories are needed to make apps work right.

Follow the advice of either running with sudo, or sudo su - to swap to running as root in login shell, it will likely resolve.