dh_installkpatches: 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/dh_installkpatches - from package: dh-kpatches

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

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