Help with script turn on/off

Unity Engine
1

Hello every one,I hope you are not offended by the fact that I will use Google translator)
I want to make a mod for the VR game, it will be lightsaber, I already have a model, I did this for this video

But they did not explain how to turn it on and off. I really hope for your help! (if interested the game is called Blade & Sorcery)

2

I need the lightsaber to activate and turn off when I press a button on the VR controller

3

Please do not duplicate threads.