A fan can be controlled in many ways.

Fan Speed Control

First the speed can be controller continuous, airflow or in upto 4 steps (levels)

When your Fan supports continuous (0-100%) it needs a 5.001 DataPointType listen and set address:

Same for Airflow, you need a DPT 9.009 set and listen address. And you specify the minimum and maximum:

When you choose level, you can specify 1 to 4 levels. They can all be controlled by 1 byte (DPT 5.010):

Or by a bit (DPT 1.001) individually :

Automatic Mode

Another option is the mode:

When you choose anything other than "Not supported", you need to specify another two group addresses (DPT 1.001) for set and listen of the mode:

This way you can set the automatic mode from HomeKit, for instance.