my point is not updating and just keep printing 1 as point even when trigger was apparently "entered

First of all, you can`t have Destroy(gameObject) in the middle of the code. It destroys your gameObject and every component attached to it, including your code. So everyt$$anonymous$$ng after t$$anonymous$$s line will not execute. Then, you are updating variable in the object you are about to destroy. As I see it,

 using System.Collections;
  using System.Collections.Generic; 
 using UnityEngine;
 
 public class WhenCollide : MonoBehaviour {
 
  public int point = 5;
  // Start is called before the first frame update
  void Start()
  {
      
  }
  // Update is called once per frame
  void Update()
  {
  }
  private void OnTriggerEnter(Collider other)
  {
      if (other.CompareTag("Animal"))
      {
          GameObject player = GameObject.FindWithTag("Player");
          
          // assume you have script called Player with method AddPoints(int points), then
          player.GetComponent<Player>().AddPoints(point);
 
          Destroy(other.gameObject); 
          Destroy(gameObject);
      }
  }