@LeonelMV Generally speaking, this is not the way to make the player aware the object is interact-able.
You will have to modify the material for each object you want to intact with! It’s certainly possible, but a very long way round. You could do it with 2 materials, you could do it with a material instance which has the fresnel setting in the instance.
A much easier way is to change the cursor on the HUD to let the player know the object is usable. The crucial components of this are:
A line trace coming from the camera ( in blueprints you can tell which object the line trace has reached - line trace by channel )
Setting up a BP interface. This sounds a bit daunting, but the is literally nothing to it ( have a look on youtube for blueprint interface ).
In your BP, you can tell if the intersected object implements your interface using the node ‘implements interface’.
You can put multiple objects you want to interact with ( that belong together ) in a BP as components. These components can have tags like ‘clickable’. Your BP code that checks the object implements the interface, can also check if the component is clickable, and chance the cursor accordingly.
There is a lot of ground to cover here, but I’ve given you some useful pointers that I spent literally months finding out about when I was learning…
Of course, you can do it any way you want. You could also use an ‘outline’ shader ( see Tron material on youtube ), to let the user know an object is ready. But this again requires messing with the material for each interact-able object…