2008 Buick Lucerne quiting

I'd have to be sure the battery has a full charge? With intermittent issues, have to test when problem is ongoing. If it cranks good but won't start, have a helper crank it while you visually check for spark at the spark plugs, if spark everywhere, use a gage and check proper fuel pressure. Check for fuel injector pulse.

What about your security system?

Can you check applicable trouble codes? Some of the national brand auto stores will check codes for free. If you want to check codes, yourself, at the least, you need an obd2 code reader.

i have code reader....no codes.....no spark and no fuel pump either....once engine lights on it will crank but no fuel pump or start....starting to think a relay somewhere shutting down....or fuse block under hood has a problem

You may have more than one problem? You could have problem with ignition switch, you were talking about the dash lights, not coming on when you turned the key?

With engine cranking, check primary voltage at ignition module and fuel injectors, pink wire.

If your ignition switch has a problem, testing anything else, first, can be problematic.