luau: 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 Debian possible default full paths are:

/usr/bin/luau - from package: deets

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

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