Need some help with diagnosing my car. Young guy learning

Thank you all for the resposes. i located the firewall connector from under the hood and cleaned them up to the best of my abilities but still nothing. i saw that there was another firewall connector looking thing on top of the pedals. maybe cleaning that up as well? or anyb other ideas on what to check? could it possibly be the ignition switch? but if it were the ignition switch, shouldnt the lights still power on regardless the swutch not working?
Yes.
See my response in your other thread.
No cranking, radio, interior lights or headlights working.
1976 Wiring is very different than previous years. 1975 I'm not sure what you have under the hood, or whether its been altered Take and post some photos.
Also might want to look at this thread for an example how meters can be used to pinpoint a problem location. Even with some communication confusion, the location was identified by the testing.
Had headlights, then high beam only, now nothing