TL:DR; it worked!
Main story: I decided to do it in my Spanish class (risky, I know), I plan on doing it for some friends too and helping them get it unblocked. Finally I can use Linux!
i also disabled auto updates by using my cellular data so it cannot update automatically, instead requires manual updates!
that’s pretty much the same thing as what i’m doing but much simpler, the school pays for the SIM/cellular data my chromebook has so it won’t download updates automatically since the wifi/data is pay to use
going to have to do some packman repo editing in order to get some stuff i need to build a sh1mmer package, since some of it does not appear to be in manjaro’s repositories
still very interested in the usb boot, really want to get manjaro or lubuntu running at school so i can unblock stuff