freefoam-settling: command not found

Have You tried accessing the binary with the full path?

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/freefoam-settling - from package: freefoam

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