How can i make tunnels with PathFinding?

I was wondering if it is possible to have Models, that are tunnels you can walk in, and generate them to a certain point with the PathFinding service, can someone give me a basic idea on how i could do this? (not script requesting)

You would use perlin worms, not pathfinding. Pathfinding is for generating a path through an existing map, not creating a new map.