Configuring gazebo and questions about gazebo_ros2_control

[lnss1-ua]

Hello, I wanted to create a custom controller but it seemed that it's impossible to make a custom controller and link it to gazebo or moveit within this repository. Could someone give some advice on how to make a custom configuration for gazebo or how to custom the gazebo_ros2_control.

Is there actually a way to make a custom controller and simulate it ?

thank you.

[lnss1-ua]

Also I wanted to ask if someone would be able to explain how does the simulation here actually works. I saw that there is a fake controller that mocks the robot but I don't really understand how does it link with the simulation.