Thank you for answering, but I already created a wheelchair with the WheeledVehicle Blueprint, and everything worked!(I wrote that at the top)
But the out of the box provided wheeledvehicle does not fit my needs, because a wheelchair is not steered by the front wheels, its steered by how much one of the rear wheels turn. And the VehicleWheel class is just a data class that alone won’t provide me a collision if I don’t use it in combination with the WheeledVehicle I think. I also tried digging around in the c++ code of the vehicle to maybe find a way to just create a round collision but until now no luck.
Take a look a the gif under the second picture to see the version I created without the WheeledVehicle blueprint, so you know what I mean with the behaviour of the front wheels.