How to make a mesh from 4 points?

I would like to have a script to build a plane with 4 points at the moment I have a script that can get the position of all the points but I don’t know how to create the plane is it possible?

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

public class ClothBuild : MonoBehaviour{
    public GameObject p1;
    public GameObject p2;
    public GameObject p3;
    public GameObject p4;
    public Vector3 pos1;
    public Vector3 pos2;
    public Vector3 pos3;
    public Vector3 pos4;

    void Start()
        //finds spheres
        p1 = GameObject.Find("P1");
        p2 = GameObject.Find("P2");
        p3 = GameObject.Find("P3");
        p4 = GameObject.Find("P4");

        //gets the positions of all spheres
        pos1 = p1.transform.position;
        pos2 = p2.transform.position;
        pos3 = p3.transform.position;
        pos4 = p4.transform.position;

For anyone looking this up in the future following this really helped