gba3: 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/gba3 - from package: gambas3-dev

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

Error in other languages:
gba3: bevel nie gevind nie
gba3: comandă negăsită
gba3: comando não encontrado
gba3: commande introuvable
gba3: command not found
gba3: käsku ei ole
gba3: không tìm thấy lệnh
gba3: komanda nerasta
gba3: Kommando nicht gefunden.
gba3: kommandot finns inte
gba3: komut yok
gba3: nie znaleziono polecenia
gba3: níor aimsíodh an t-ordú
gba3: no se encontró la orden
gba3: no s'ha trobat l'ordre
gba3: opdracht niet gevonden
gba3: parancs nem található
gba3: perintah tidak ditemukan
gba3: príkaz nenájdený
gba3: příkaz nenalezen
gba3: команда не найдена
gba3: командата не е открита
gba3: 命令找不到
gba3: コマンドが見つかりません