Trouble putting a ROM on Nexus 6p I just bought a Nexus 6p a few days ago. I put TWRP and Cyanogenmod 14.1 on it. It was fine, until I wanted to try another ROM. So I booted to TWRP, and wiped it. I wasn't thinking when I wiped and now I don't have a ROM to flash. I want Resurrection Remix ROM. How can I fix this? I am really worried. Any help is greatly appreciated. If you need any more information just ask, I will gladly provide more if I can. I am open to installing any (safe) custom recovery, and any ROM at this point. Also, where is a place on the phone that does not get deleted when I perform a factory reset, so that I can always have a backup in case this happens again.

Thanks for any help!

I forgot to add:
When I try to use fastboot update rom.zip I get this:
Boot into TWRP again, choose "Advanced-ADBSideload", connect to PC, then adb sideload path/to/your-rom.zip (just open a command prompt window for this, and drag the zip file into the window to have its file name and path entered automatically).