Flip the levoit air purifier over (fan is on the top side with the buttons.) You’ll see there’s a locking mechanism on the bottom, simply twist to unlock it. The first filter will be black, just simply remove by pulling up. The second is the white (or now possibly yellowish filter after months of use more than likely.)
It simply lifts up and out by pulling the white tabs located on each side up and out.
Replacement filters look identical (flintar makes some good ones just make sure to match your model number).