How do I send a variable (after calculation) as the final variable to another game object

I don’t think i worded my question correctly, but I have a player script monitoring colliders using Physics.OverlapSphere and this in turn does send a message and the function on the other script damages the object. What i am trying to do is have the player hold a universal value, like damage = 2, but i want to do a calculation in a method in the player script, so finalDamage = damage * 2 for example. I want to know if there is a way for me to, after the value is calculated, physically send that unique value to what was hit, rather than having to have each object hold its own value to be damaged by.

Well indeed there are many ways to “physically send values”.

I would recommend you just reference the value directly, here let me explain with some code:

Suppose this is “script01” and you have the “damage” as a public variable:

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

public class script02 : MonoBehaviour
{
    public float damage;
}

Now to get that "damage" from another script, you simply need to do this:

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

public class testScript : MonoBehaviour
{
    [SerializeField] private script02 s02; //Don't forget to assign in inspector

    private float damage;

    void retrieveDamage()
    {
        damage = s02.damage;
        //this will set our damage on this code, to the "damage" of that code.
    }
}