Deal damage (damage_manager)

Hi guys! I have problem with my damage_manager script, he should receive information from a opponent script. unfortunately I don't know where Im doing wrong. Im attaching two scripts. Manager script:

  using System.Collections;
  using System.Collections.Generic;
  using UnityEngine;
  
  public class damage_manager : MonoBehaviour
  {
      //public float health;
      public static float damage;
      private float armor_dmg;
      private float health_dmg;
  
      void FixedUpdate()
      {
          //if (health <= 0)
          //{
          //    Destroy(gameObject);
          //}
      }
      void OnCollisionEnter(Collision hit)
      {
          player_mechanics stats = GetComponent<player_mechanics>();
          if (hit.gameObject.tag == "Enemy")
          {
              armor_dmg = damage * 0.7f;
              health_dmg = damage * 0.3f;
              Debug.Log(stats.Armor + " " + stats.Health + " " + health_dmg + " " + armor_dmg);
              if (stats.Armor > 0)
              {
                  if (stats.Armor >= armor_dmg)
                  {
                      stats.Armor -= armor_dmg;
                      stats.Health -= health_dmg;
                  }
                  else
                  {
                      stats.Health -= ((armor_dmg - stats.Armor) * 0.5f + health_dmg);
                      stats.Armor = 0;
                  }
  
              }
              else
              {
                  stats.Health -= damage;
              }
              if (stats.Health < 0)
              {
                  stats.Health = 0;
              }
          }
  
  
      }
  }

This is the second script where i want to set damage:

  using System.Collections;
  using System.Collections.Generic;
  using UnityEngine;
  
  public class damage_test : MonoBehaviour
  {
      public float Damage_value;
  
      private void Update()
      {
          damage_manager.damage = Damage_value;
      }

The end result should be that each damage script should send its own damage information to the manager script. Thank you for any help :)