The case itself does come with 2 140mm fans. They are amazing and as mentioned adding more 140mm in a case with airflow this good makes for very silent operation. If you have 120mm i would suggest to move the included case fans to the front for intake and install the 120mm to the rear and the top. Allows good airflow to enter the case and the exhaust of the air can be run at lower fan speed with the 120mm

Yes 120 and 140, I recommend using 140's, with similar airflow, the 140mm is quieter as it needs to spin slower, I added a 140 to the case to have 3 in total, they spin constantly at their minimum speeds, are inaudible, and the cooling is more than ok 🙂