TeleportTarget.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class TeleportTarget : MonoBehaviour 
{
    public string button = "Fire1";

    public Transform lookDirection;
    public Transform target;
    public float maxSlopeAngle = 30;

    public void Update()
    {
        if( Input.GetButton(button) ){
            Teleport();    
        }

    }

    void Teleport()
    {
        RaycastHit hitInfo;
        bool hit = Physics.Raycast(lookDirection.position, lookDirection.forward, out hitInfo);
        if( hit ){
            float currentSlope = Vector3.Dot( hitInfo.normal, Vector3.up );
            float maxSlope = Mathf.Cos(maxSlopeAngle*Mathf.Deg2Rad);
            if( maxSlope > currentSlope ){
                target.position = hitInfo.point;
            }
        }
    }

}