Pressing a button changes Widget on HUD in FPS Game

Can someone point me to a tutorial where this is explained?

I have a FPS game with a grey flashlight icon on screen, and when I press the F button, I want to change that flashlight icon to a white flashlight icon, indicating the flashlight is turned on.

I’m really messing around with the Widget Switcher and stuff, but I can’t get it to work, it’s constantly telling me I’m inputting invalid targets for the blueprint nodes…

If someone could give me an example how this would work, or point me to a youtube video where this is made, I would greatly appreciate it.