Help on installing macos ventura

Hi everyone, I have a late 2012 mac mini which is currently running sonoma however one day My lockscreen background turned black and my dock also went black on the background anyways i tried reinstalling rootpach and had an update pending error of whatever I did it wouldnt go away. Somr people recommended to reinstall sonoma, however I have some questions, I want to install ventura instead and have downloaded the installer file from mr macontosh on my windows pc, however when I try to transfer it to usb stick I get some file too large error, so what do I format it to and how to format it so that the installer can transfer, along with that im not really familiar with macs so does anyone know what to do after transferring the file to the usb, as af tree r that I have no clue what to do, another question is is that there is icloud account which is my brothers on the mac, however since root patch dont work I cant log out, and he doesn’t know the password, so if I try to reinstall will ickoud affect anything? Thanks, if someone could find me a tutorial on what to do then please do, thanks.