BootSectImage: 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 CentOS possible default full paths are:

/usr/bin/BootSectImage - from package: edk2-tools

You may install the required package with command yum install {package}

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