Wheres the shop where you can change your body parts, and make them bionic or something

It's in Shadowglen with all the zombie stuff in Underground. Here's a link to the shop you want: http://subeta.net/explore/underground/doctor.php. It only works if you're a zombie.

thanks, how do you become a zombie?

You become a zombie during the Pandemic event, which is in February. c:

:o Thanks for telling me that