PlayerBrain.cs

using UnityEngine;
using UnityEngine.AI;

public class PlayerBrain : CharacterBrain
{
    public PlayerBrain(NavMeshAgent navMeshAgent) : base(navMeshAgent)
    {
        navMeshAgent.GetComponent<Renderer>().material.color = Color.green;
    }

    public override void Tick()
    {
        if (Input.GetMouseButtonDown(0))
        {
            Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);

            RaycastHit hitInfo;
            if (Physics.Raycast(ray, out hitInfo))
            {
                navMeshAgent.SetDestination(hitInfo.point);
            }
        }
    }
}