kvm: 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/kvm - from package: qemu-kvm

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

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