How to Change AI Movement Speed with BEHAVIOUR TREE in the GAME ANIMATION SAMPLE | Unreal Engine 5 

You're welcome!

I'd probably start with learning how to get the NPC to follow the main character and be able to do the same kind of traversal that the main character does. Here's a video from a different creator that goes over some of these things: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-1w_MwfwD3c8.html