Replace the E Key Event in the example above and try using a Space Bar Key Event instead. When you play in the Editor, notice what happens. You can Jump by pressing Space Bar when outside of the trigger for the light, however when you enter the trigger and press Space Bar, you no longer Jump but instead call the Print String and text Hello; this is due to Input Priority.
When Input commands are shared (as is the case here with Jump and the input we assigned in our Light both tied to Space Bar), lower priority actions are ignored. Inside the light Blueprint, if you click on the Space Bar Key Event and look in the Details panel, you should see an option for Consume Input.
If you un-check the Consume Input checkbox and play in the Editor again, you should now be able to Jump both inside and outside of the light's trigger volume. When inside the light's trigger volume, by pressing Space Bar you will also call the Print String node and the Hello text to be displayed.
Also in the Input Details window are options for Execute when Paused (which allows you to press the Key during the paused state and execute commands) and Override Parent Binding (which allows you to remove any bindings set in any parent classes).