livereload: 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/livereload - from package: python3-livereload

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

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