unity change a variable in another script code example

Example 1: unity variable from another script

//Make Health public
public class PlayerScript: MonoBehaviour {
  public float Health = 100.0f;
}

//Access it.

public class Accessor : MonoBehaviour {
    void Start()
    {
        GameObject thePlayer = GameObject.Find("ThePlayer");
        PlayerScript playerScript = thePlayer.GetComponent<PlayerScript>();
        playerScript.Health -= 10.0f;
    }
}

Example 2: unity how to use variable from another script

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

public class Miner : MonoBehaviour // A class made to mine coins
{
	private Variables variables; // "Variables" is the class name with my variables in it, "variables" is the name of it's variable in this class

	void Start()
	{
		variables = GameObject.Find("ScriptHolder").GetComponent<Variables>(); // "ScriptHolder" is the name of the GameObject that holds the Variables class
	}

	public void Mine()
	{
		variables.coins += variables.minePower; // This is how you reference your variables
	}
}