How to install the Script extender for Fallout 4 and NMM?

Greetings. I am trying to mod my STEAM version of FO4. And, I need to install the Script extender, and I was looking at the reddit modding instructions that I found, the instructions do not specifically tell me how to install it for FO4 and NMM. And thus, I am confused as hell, I don't want to blow something up.

Thank you