Is North Korea really planning an EMP attack (More details)

EMP= Electromagnetic Pulse
It is a quick burst of electromagnetic energy, that if set off in the U.S (Granted it’s large enough), it could completely shut off all our electricity (from what I understand), and could possibly kill us. I heard that NK has a satellite over the U.S and that they have threatened our president about using it to do something if we try to attack them. I also heard that Obama passed some executive order about it. I’m not sure if this is real or not. I’m not finding a ton of information about this, so If anyone can add information/details that would be helpful. I want to know more about this if it’s real.
I’m sorry for not providing a lot of details/ knowing a bunch of information, I use a school-provided computer and a lot of things are blocked, so I am unable to find a lot about this