Most new cars are indeed California certified and meet California emission standards.
If you buy a new car in California then it will certainly meet California Emission standards and pass California emission testing.
If the car doesn't meet California emission testing standards then it will not be allowed to be brought into or sold in the state of California.
So if you buy a brand new car from a dealer in the state of California it should always meet the emission standards of California.
If the vehicle is California certified or Federally certified they'll be a sticker or control label under the hood in the engine compartment.
So you can ask the dealership to show you the label and prove that it's California certified which it should be if it's sold in California.