PW3 Where do I download the proper jailbreak file?

Hello, I've been following this guide step by step

https://wiki.mobileread.com/wiki/5_x...re_to_computer

And there's no link provided for the "Download and install firmware jailbreak" part. It just says to download it, and I can't find it anywhere on the internet, what am I doing wrong?

I've been searching for hours, I wouldn't post this if I wasn't desperate, lol.

Thank you