selinux-config-enforcing: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/sbin/selinux-config-enforcing - from package: selinux-basics

You may install the required package with command apt-get install {package}
Error in other languages:
selinux-config-enforcing: bevel nie gevind nie
selinux-config-enforcing: comandă negăsită
selinux-config-enforcing: comando não encontrado
selinux-config-enforcing: commande introuvable
selinux-config-enforcing: command not found
selinux-config-enforcing: käsku ei ole
selinux-config-enforcing: không tìm thấy lệnh
selinux-config-enforcing: komanda nerasta
selinux-config-enforcing: Kommando nicht gefunden.
selinux-config-enforcing: kommandot finns inte
selinux-config-enforcing: komut yok
selinux-config-enforcing: nie znaleziono polecenia
selinux-config-enforcing: níor aimsíodh an t-ordú
selinux-config-enforcing: no se encontró la orden
selinux-config-enforcing: no s'ha trobat l'ordre
selinux-config-enforcing: opdracht niet gevonden
selinux-config-enforcing: parancs nem található
selinux-config-enforcing: perintah tidak ditemukan
selinux-config-enforcing: príkaz nenájdený
selinux-config-enforcing: příkaz nenalezen
selinux-config-enforcing: команда не найдена
selinux-config-enforcing: командата не е открита
selinux-config-enforcing: 命令找不到
selinux-config-enforcing: コマンドが見つかりません