The following is an example of using the Path object to find the path from A to B.

using Nav3D.API;
using System;
using UnityEngine;

class YourGameScenario : MonoBehaviour
{
    private void Start()
    {
        Nav3DManager.InitNav3D(1f);

        Vector3 a = new Vector3(-10, 10, 10);
        Vector3 b = new Vector3(-10, 10, 10);

        FindPath(a, b, PrintPath);
    }

    //your method for pathfinding from A to B
    void FindPath(Vector3 _A, Vector3 _B, Action<Vector3[]> _OnPathFound)
    {
        //create Path instance
        Path path = Nav3DPathfindingManager.PrefetchPath(_A, _B);

        //perform pathfinding from _A to _B
        path.UpdatePath(_OnSuccess: () =>
        {
            //notify that path was found
            UnityEngine.Debug.Log("Path successfully found!");

            //invoke callback
            _OnPathFound(path.Trajectory);

            //finish work with Path instance
            path.Dispose();
        });
    }

    void PrintPath(Vector3[] _Path)
    {
        for (int i = 0; i < _Path.Length - 1; i++)
            UnityEngine.Debug.LogError($"Path point {i}: {_Path[i]}");
    }
}