How do i link 2 scripts together

I have a Script A located in my finish line object and i have Script B located in my player (so how do i link them?)

Script A:
Script Starts:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

public class FinishScript : MonoBehaviour {
public int TpNum = 0;
public bool Credits1 = false;
public Transform destination;
public int Credits = 0;
public Text CreditsText;
public bool Sell = true;
public bool Buy = true;
public bool BuySkin1 = true;

// Use this for initialization
void Check()
{
    if (Credits >= 100)
    {
        Debug.Log("Continue Playing");
    } else if (Credits < 100)
    {
        Debug.Log("Not Enough Points!");
    }
}
public void Update() {
    CreditsText.text = "Credits: " + Credits;
    destination = GetComponent<Transform>();	
}

// Update is called once per frame
public void OnTriggerEnter(Collider other)
{
    if (other.tag == "Player")
    {
        TpNum++;
        Credits = Credits + 10;
        if (TpNum == 1)
        {
            other.transform.position = new Vector3(30.07f, -4.38f, -1.520389f);
        }
    }
}
public void BuyState()
{
    Credits = Credits + 0;
    if (Buy == true)
    {

        if (Credits >= 100)
        {
            Credits1 = true;
            if (Credits1 == true)
            {
                Debug.Log("Purchase Complete");
                Credits = (Credits - 100);
                Sell = (Sell = true);
                Credits1 = false;
                Buy = (Buy == false);
            }
            else
            {
                if (Credits1 == false)
                {
                    Debug.Log("Gather More Coins");
                }
            }
        }
    }

}

public void BuyState1()
{
    Credits = Credits + 0;
    if (BuySkin1 == true)
    {

        if (Credits > 99)
        {
            Credits1 = true;
            if (Credits1 == true)
            {
                Debug.Log("Purchase Complete");
                Credits = (Credits - 100);
                Credits1 = false;
                BuySkin1 = (BuySkin1 == false);
            }
        }
    }
}

public void Incomplete()
{
    Credits = Credits + 0;
    if (Credits < 100)
    {
        Debug.Log("Incomplete Gather More Points Or Buy More");
    }

}

}

Script B:

public class Check : MonoBehaviour {
public void Check2()
{
if (Credits >= 100)
{
Debug.Log(“Continue Playing!”)
}
}
}

@Bunny83 @Eric5h5 @robertbu @aldonaletto @whydoidoit @duck @fafase @clunk47 @Mike 3

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Link: How do i link 2 scripts together - Questions & Answers - Unity Discussions
Thanks Nicholas