Working on a friends 02 ss monte, the key wouldnt turn over to start car, so I replaced the ignition switch from junkyard, installed it, and nothing,had all kinds of crazy dash lights, but would not start,tried to relearn the computer with the key on for 10 minutes,3 times like most people said, no start, wondering what to do next

been working on a friends 02 ss monte, the key would not turn over,so I replaced the ignition switch, nothing, will not start, tried learning the pass code to learn the computer,disconneted the battery, tried to start, nothing, tried to jump solenoid with screw driver, little spark, think battery dead for now, is the bcm bad?, need to relearn the pass lock?