i need to learn who do you send a keylogger to some one with out them knowing and how to rechreve it? I need to do both of these thing from my computer though!

i need to learn this because my friend that i want to go out with has a boy friend and i have been hereing thing that he she cheating on her so i need to try and find out!!!

thanx for reading this and if can tell me how to then thanx more or ig you know a better way of finding out plz tell me!!!!