batch file to run updates of several models

Hello i have this code:


Code:
@echo off
rem *** jump to model according to PA number ***
set "pa"=
set /p "pa"=PA Number:

:PSAT1
:PSAT2
cd biostosh\bios1.exe

:PXLL1
cd biostosh\bios2.exe


the objective is to put this batch file in a USB drive in order to run the new bios for PC. Some models use the same bios file. This code works, but if i put the "PSAT1" goes to bios1.exe, and PXLL1 goes to the same file, when should go to bios2.exe.What can i do to put this to work?
There will bem more than 100 different models so i need a way to put it to work in
Need help please, i am a novice in this bath things..