I have a cylinder 6 misfire on my 00 cadillac deville. do u think the plugs need to ne replaced?

I don't think you really understand what this fault code means, it means that likely all the engine cylinders are misfiring at random no set pattern, not any particular cylinder. I would start with checking for engine vacuum leaks like the intake manifold gasket. that is all I can say since you provided no make, model or year and engine type and size information.

miss fire check coils or plugs

With a noid light .
9pc Electronic Fuel Injection Signal Noid Lite Tester Light set GM Ford... or you could use just a test light . Video's on youtube showing how.

swap the coil pack from the other side of the engine and see if your misfire moves to cylinder 1

MMY 2003 DTS HAD SAME PROBLEM. REPLACED FRONT COIL PACK AND FIXED THE PROBLEM. LATER #3 CYLINDER STARTED MISSING, REPLACED REAR COIL PACK AND SOLVED PROBLEM HOPE THE HELPS

Take to a repair shop

Beyond your expertise

DO SPARK PLUGS AND WIRES CHANGE IF NOT HAVE DONE TUNE UP IN A LONG WHILE. CLEAN FUEL INJECTORS.CLOGGED FUEL INJECTORS WILL CAUSE CYLINDER MISFIRE ALSO.

It sounds lke you need to do a tune up. Sometimes when a vehicle sits for long periods the plug wires can weather crack. Run the car at night and watch for arcing on the plug wires

Replace your wires and plugs.The bit of smoke coming out is telling you that it is firing but only occasionally.First replace plugs because they are cheaper.

check out this tool. Brand new on the market and it quickly can diagnose a misfire from the plug or the coil pack. Here's their website