To follow up up Shadow Boss12’s suggestion, here’s the same explanation but with images.
As far as I understand, you wish to be able to fire a spell (from the player controller) whenever the skill button (in widget) has been pressed.
I’d suggest to create a boolean variable on the player controller, as shown in the image below. This way you can easily check if the button has been pressed in the widget.
To set this variable, add a reference to your player controller in you widget just like the image below. Then whenever the button in the widget is pressed, set the boolean variable you created in the player controller.
Now, you can use this boolean variable in your player controller, whenever you press any key (or perhaps an input action key?). Look at the image below for BP implementation.
Hope this makes sense, and this is what you’re looking for.