FreeCADCmd: 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 CentOS possible default full paths are:

/usr/bin/FreeCADCmd - from package: freecad
/usr/lib64/freecad/bin/FreeCADCmd - from package: freecad

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/FreeCADCmd - from package: freecad
/usr/lib/freecad/bin/FreeCADCmd - from package: freecad

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

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