freight-add: 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 CentOS possible default full paths are:

/usr/bin/freight-add - from package: freight

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