Raspberry Pi can be deployed with / without Fan. of course having Fan is always better option. So we can avoid the device from overheating.
When i make order for my Raspberry Pi, it is in bundle package (Complete will all the necessary kits)
When the Raspberry Pi delivered it has Fan that need to be attached.
The manual:
Connect the fan's red wire to GPIO pin 4 (5V) and the black wire to GPIO pin 6 (ground).
How to check Pin assignment
After power on the device Fan will be on.