librecad: 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/librecad - from package: librecad

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