Okay! So I couldn’t copy & past the results directly because of the lack of internet, but I did take a photo with my phone! (edit: looks like I can’t upload media so I’ll try to retype the important bits)
result of inxi -Nazy
Network:
Device-1: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet
vendor: ASUSTeK driver: r8169 v: kernel prot f000 bus ID: 04:00.0
chip ID: 10ec:8168
Device-2: Realtek RTL8812AU 802.11a/b/g/n/ac 2T2R DB WLAN Adapter type: USB
driver: usb-network bus ID: 1-2:2 chip ID: 0bda:8812 serial: <filter>
I don’t think I need to copy every single result of lsusb so here’s the one that I think corresponds to my device? I can do more if that’s not right
Bus 001 Device 002: ID 0bda:8812 Realtek Semicondoctor Corp. RTL8812AU 802.11a/b/g/n/ac 2T2R DB WLAN Adapter
Looking at this, I think what I need is a driver for the RTL8812AU? Is that right? I do see some results when I google it so at least I know it’s not a totally meaningless string 
So if that’s right, how would I get the drivers for it onto my computer without an internet connection? Or am I going to have to invest in a really long ethernet cable 