selinuxenabled: command not found

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 CentOS possible default full paths are:

/usr/sbin/selinuxenabled - from package: libselinux-utils

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/sbin/selinuxenabled - from package: selinux-utils

You may install the required package with command apt-get install {package}

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