So i knew how to turn light on off with blueprint, but i have to go close to the light to do it. Now i want to turn it on/off but with another mesh (like a switcher). How can i do it? i tried to create some blueprint with my little knowledge and its wont work. So im here to ask for help 
So obviously your switch needs to know its associated light.
So create an editable variable in your switch that is of the class of your light blueprint. In the editor, find your light blueprint instance and enter its name into the switch’s variable. In the switch’s blueprint you can now change the light’s parameters. This should in your case be obviously coupled to a trigger.
thx u alot, that exactly what i need. Idk we can call a blueprint in another blueprint