Where do I find the bootcode in the os file?

Boot code is not included in 8xk (or 8ek) files. This is why you need to dump a ROM for use with emulators, because emulators require boot code to work.

I was wondering because I need to Trick TI-Connect-CE into thinking that the operating sytem I am trying to install is an Official Up-to-date OS.

Bootswap is Unable to Disable OS-Verification & when I try to install an older bootcode from the AppVars it fails.
And I cant Find an Actual Transferable Version of Cauldron.

EDIT:

Is there an Alternate Program to Send an OS to the TI-84+CE?

You can't just trick TI-Connect CE into transferring another OS. the calculator does the verification, so you have to trick THAT, or just make it not verify the OS. If you have a TI-84 Plus CE revision <M, then it would be possible to lower the minimum required OS version with CERMASTR. You can't change the bootcode on revision M+ calculators though.

So How do I Use Cermaster?

I Installed it on My Calculator, but What Section is the MinOS?

I don't believe there is (nowadays anyway) a publicly available version of CerMaster that can be used to change the minOS field. (And if there is, it's a mistake that should be fixed)

Regardless, this isn't related to needing the boot code.

There is an editable minOS field, but I don't know what to change it to.

This is the Current entry:

037 010805
(03)* * ►

The Stars are:

1. a weird n symbol
2. a weird f symbol

So I changed it but I cant Install TiLP or TI Connect CE on the computer I am using, is there another way to send the OS?

No, you can't. But more importantly, there's also no need. Get arTIfiCE and install (Cesium and) AsmHook if you want to run ASM programs like before OS 5.5.

And if this isn't the reason why you want older OS versions, something tells me it could be cheating-related. In which case, nobody will help you cheat.

I Wanted an older version so I could dual boot with BOS OS or TI-OS2.

I Got it downgraded from 5.8.1.0012 to 5.3.0037 Using CERMASTR 2.0 thanks to a youtube tutorial.

Sorry to be the bearer of bad news, but;

BOS does not support dual-boot at this time. There isn't much of a point to especially with all the wonderful shells people have created.

Additonally, BOS will NOT run on an calculator on revision M or newer. CE Calculators shipping with OS versions 5.4.1 and up CANNOT run BOS. This is because the flash chip is completely different from the one used before revision M. Additionally, there is no way to disable boot time verification on calculators with the new flash chip. The boot sectors are NOT unlockable in software. The only way is to de-solder the flash chip, program it with specialized hardware, and solder it back in; which is a royal pain even for those experienced with soldering.

Good news though, you can use BOS in CEmu if you use the ROM image, which is built with an open source bootloader and does not contain proprietary code.
I should really get around to making another release though, stay tuned for that.

My Caluclator Originaly had 5.3.1 installed when I got it, My teacher had us all update them to the newest version, ever since I have been looking for a way to downgrade it, & luckily I was able to, That is to bad that BOS does not have dual boot(although it is the closest to it as you can reinstall TIOS).