no start

hi gays i have 2007 chevrolet cobalt it came from another gareg to me i ask the owner of the car what is the history of the car he said he gave the car to a technichan to put the radio to step one of the ignation key so the car start 2 time and from that time the car did not crank i make a comment on yutube on scanner danner he ask me to remove the radio wire and re progrmm the key and i did the car did not crank and the theft light on dash is on pls i need help

Start with a full system DTC scan. We want to know what faults are setting and, more importantly, if all the modules are talking on the network.

Post the results of your DTC scan and we can go from there.

i can communicate with the car i try to daignose it it will show me the is no code from the vehicle