GenPatchPcdTable: 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/GenPatchPcdTable - from package: edk2-tools-python

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

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