surf: 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/surf - from package: surf

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

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