98 Forester no power?

Wifey took it too do some errands and shut it off and it failed to start jumped it it and it ran fine for a bit. The battery was bad so we changed it but prior to that it would fade the radio out in between shifting. Changed cables they were corroded tried to start it and nothing just the litttle sound telling me that the key was in the switch not lights no accessories nothing at all? Hoping someone can give me a lead I heard something that it might be the ignition not sure just tired of searching and coming to dead ends.