Yes, it depends on cpu governor and thermal zones, basically it’s prepared for radxa stock fan that most buy with board. Of course I would check out that because it’s possible that not every image support this particular functionality (it should).
Of course If You need to alter something related to that (if You have non standard fan, or just want to get different speed levels) You can do that on source code. Something similar in 5B Rock 5B FAN Control was discussed here and probably it’s same on 4C.
It’s not Raspberry, and of course it’s not pi3 which was cool don’t needed cooling.
Take a look at other Radxa products, temperature control is present on many of them and You can easily find source code for those if You really needed that. As I said most will just use stock fan, connect it to header and forget.
Sata HAT has own fans and temp sensors, this may be useful if You need to build external fan and control it.