The system works via events. As in when the key assigned to use it (Q in this example), sends an event on each type of press. Either down, up, or hold.
In this example, the Push Objects Systems, calls to the Action System to play a specific animation and push objects around. The component also allows you to make small script behaviors if needed for specific interactions or to use the already created elements as you prefer.
By default Game Kit Controller loads all the demo abilities for you to use or alter. If you want to clean out the list just follow so.
On this list, you can see the all examples usable out of the box. So you can remove any of those which are enabled by default, each of those abilities has an ability-enabled field
With that as false, the ability is not usable and can be unlocked by events or anything similar, including the experience or skill system for it.