Is having 150g of carbs a day bad when trying to get six pack ?

If you wan't to get a six pack you have to cut you carb intake almost completely and replace that with protein and fat (although you should keep the fat as low as possible too). Also you'll need to workout.

When your body doesn't receive carbs, which is its primary fuel source it'll have no other option that no start dissolving fat stored inside the body. Keep it up for long enough and bam a sixpack

Yes.