NanoPark/Assets/Scripts/SliderIndicator.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
public class SliderIndicator : MonoBehaviour
{
    public Slider slider;
    public Text text;
    void Start()
    {
        slider.onValueChanged.AddListener(OnChanged); 
        text.text = slider.value.ToString();  
    }

    void OnChanged(float value){
        text.text = slider.value.ToString();
    }

    void OnValidate(){
        if(GetComponent<Text>()!=null && text==null)
            text = GetComponent<Text>();
    }
}