gforth-itc-0.7.2: 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/gforth-itc-0.7.2 - from package: gforth

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

Error in other languages:
gforth-itc-0.7.2: bevel nie gevind nie
gforth-itc-0.7.2: comandă negăsită
gforth-itc-0.7.2: comando não encontrado
gforth-itc-0.7.2: commande introuvable
gforth-itc-0.7.2: command not found
gforth-itc-0.7.2: käsku ei ole
gforth-itc-0.7.2: không tìm thấy lệnh
gforth-itc-0.7.2: komanda nerasta
gforth-itc-0.7.2: Kommando nicht gefunden.
gforth-itc-0.7.2: kommandot finns inte
gforth-itc-0.7.2: komut yok
gforth-itc-0.7.2: nie znaleziono polecenia
gforth-itc-0.7.2: níor aimsíodh an t-ordú
gforth-itc-0.7.2: no se encontró la orden
gforth-itc-0.7.2: no s'ha trobat l'ordre
gforth-itc-0.7.2: opdracht niet gevonden
gforth-itc-0.7.2: parancs nem található
gforth-itc-0.7.2: perintah tidak ditemukan
gforth-itc-0.7.2: príkaz nenájdený
gforth-itc-0.7.2: příkaz nenalezen
gforth-itc-0.7.2: команда не найдена
gforth-itc-0.7.2: командата не е открита
gforth-itc-0.7.2: 命令找不到
gforth-itc-0.7.2: コマンドが見つかりません