gcp: 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/gcp - from package: gcp

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

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