Wonder how to get the screen position of my character

Hello,everybody,i’m new to the Unreal Engine 4 and i’m try to learn this engine by the video tutorial - Twin Stick Shooter.
Until yesterday,it all goes well and I’ve learned quite a lot from it.
Today,I’m going to add some function and try to control my character’s rotation by mouse move.
I plan to calculate it by the vector - mouse position minus character position,of course,both on the screen.
As so far,I can get the mouse position on my screen,but when it comes to the character,i start to get confused.
I’ve tried as many functions as I can (such as ConvertWorldLocationToScreenLocation),but none of them works correct.
Thx a lot if anyone can point it out for me!:slight_smile: