ffbamg: 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/ffbamg - from package: freefem++

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

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