prads: 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/bin/prads - from package: prads

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