How do I install android onto my nexus 7?

So... I was being dumb and desided to try to install a custom recovery and screwed up. And of course, i didnt back it up. So, how do install android back onto the nexus? It has twerp recovery and thats about it. The google logo turns on when I turn the nexus on but it just stays there. Pleas help!!!

You need to use bootloader to flash stock image (basic directions and images here: https://developers.google.com/androi...s#instructions) through fastboot or try Wug's Nexus Root Toolkit which can flash from a bootlooped screen.