Complete Assembly and Boot Guide: Pironman 5 with NVMe SSD fails to

The narrator in the ‘Complete Assembly and Boot Guide: Pironman 5 with NVMe SSD’ (https://youtu.be/tCKTgAeWIjc) hurriedly states that the first thing you must do (before visiting Rapsberry Pi’s site to dl the Imager) is update the Raspberry Pi 5’s bootloader by copying it to an SD card. That’s all he says. He doesn’t say where to find it. Presumably, it’s a location that is hosted somewhere by Raspberry Pi but not accessed via the Imager. Where do I find the latest bootloader for the Pi 5?

For information on how to install your system to an SD card, or SSD, please see our online tutorial:
https://docs.sunfounder.com/projects/pironman5/en/latest/install/install_raspberry_os.html

Thanks, but that’s the same video for which I shared the link. It gives conflicting information from what the written directions say to do. The main question I have is: Is it truly necessary for me to disassemble the whole thing or can I update the bootloader, install the OS, etc. NOW, without damaging any circuits, with the whole thing is already put together?

Yes, you have assembled the pironman5 case. You have assembled the pironman5 chassis, now you said you don’t know how to install the system to the SD card or SSD, and then connect the pironman5 to boot the system?
You don’t need to dismantle the case, just follow our tutorial to download and install the system and connect it to the pironman5 case.
What step are you currently stuck on, not how to install and boot the system?

I did not say that I did not know how. What I said was that the documentation states the opposite of what the website says. The written instructions say nothing of installing the operating system on the Raspberry Pi first. I have previously installed the Raspberry Pi in the PiDog. I now have the Pironman 5 working. I ran the update for the EEPROM off of the Sandisk, shut down, removed the Sandisk and rebooted. It successfully booted from the Samsung 990 Pro and I have updated all of the files. I am now trying to get the Arduino IDE running on it , as that is the purpose for which I bought it.

Thank you for your interest.

What specific issues are you encountering while using the Arduino IDE on the case?
Please describe the problem in detail. You may also post your question on the official Raspberry Pi forum for further assistance.