How to get reference of another actor in Firstperson BP?

So For my Project i want a radio that plays a sound quicker the closer the player is to a certain actor (in this case its a monster). I have the blueprint almost sorted i just dont know how to get the monster character in my first person blueprint so i can get the distance between the two. the reason i want the distance is so i can put it in the delay so the closer we are the quicker it plays the sound. If anyone knows a solution it would be much appreciated.