How to show current car controls

I am currently using some modded cars and planes that use aftermarket parts that extra controls. What button can I press that can show the keybinds for the extra parts? This includes airplanes flaps and rudders or rocket engines

 

Go to settings find bindings and there

 

there is the UI app that is by default in the top left corner that tells controls. if it is there there should be a little arrow to push to show them all. other than that and going into the settings like a plane guy said i dont know any other way.

 

Thank you. Apparently My UI app that is supposed to be popping up is not showing for me. If I look into my bindings and look at my vehicle specific I can find them.