intel_panel_fitter: 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/intel_panel_fitter - from package: intel-gpu-tools

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

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