How to catch data in asynchronous code?

Question

JavaScript

There are two html and js documents in the project:
I use NW.js

js

var allarrWinLoseLines = [];
var arrTheorys = nearest2(['C', 'E', 'G', 'N', 'S', 'V', 'AE', 'AG', 'AJ'])

function searchGoodTheory () {

    const XlsxPopulate = require('xlsx-populate');

    XlsxPopulate.fromFileAsync("./ArchiveRates.xlsx")
        .then(workbook => {
/*
Тут мой код, который берет данные из экселя, обрабатывает и записывает в глобальную переменную массива allarrWinLoseLines
*/
            //return workbook.toFileAsync("../tennis_pars_fast/Excel/f.xlsx");
        });
function searchGoodTheory ();

function objectWithLine (nameTheory, massWinLoss){

    function colorLine (){
        var string1 = 'rgba(';
        var string2 = ')';
        var c1 = randomInteger(1, 255);
        var c2 = randomInteger(1, 255);
        var c3 = randomInteger(1, 255);
        var c4 = randomInteger(1, 255);

        var END = [];

        return END[0] = string1 + c1 + ',' + c2 + ',' + c3 + ',' + c4 + string2;
    };


    var b = {
        label: nameTheory,
        data: massWinLoss,
        borderColor: colorLine(),
        borderWidth: 1,
    };
    return b;
};

function massObjectWithLine(endCounter) {
    var a = [];


    for (var s = 0; s < endCounter; s++){

        a[s] = objectWithLine(arrTheorys[s]+'', allarrWinLoseLines[s])//счетчик побед/проигрышей (вертикаль) к каждой теории
    };

    return a;
};

The arrTheorys[s] variable takes data quietly, because synchronous
The variable allarrWinLoseLines[s] is not defined because the code takes data without waiting for the completion of the searchGoodTheory ()
function. If we wrap the massObjectWithLine function:
setTimeout(function() {
massObjectWithLine():
}, 5000);
Then the variable allarrWinLoseLines[s] is defined, but this is only if you run the function in the document itself without html

HTML

<canvas id="myChart" width="1000" height="500"></canvas>

<script>

var temp = 5;

var ctx = document.getElementById("myChart");
var myChart = new Chart(ctx, {
    type: 'line',
    data: {
        labels: gameCounter(temp),
        datasets: massObjectWithLine(3) //количество теорий
    },
    options: {
  responsive: false,
        scales: {
            yAxes: [{
                ticks: {
                    beginAtZero:true
                }
            }]
        },
        legend: {
            display: true,
            position: 'bottom'

        },
        tooltip: {

        }
    }

});



</script>

But when I run the html page, allarrWinLoseLines[s] is always undefined. How to fix it?
I read about async / await but did not understand how to use it for me (( tell me, please)