Question How would I make my own navigation?

Hello, I am planning to start making low poly horror games like Dave Microwave's Games (Look him up) but one problem, he uses UE4 and I wish to use Unity, but the NavMesh gives me headaches, how can I make my own navigation with waypoints where the agent will find a full path to take (into a room or something) then if the room is a deadend, or by chance, he will turn around and find a new path? I'm talking a full path, not just a couple waypoints