In Ionic and Vue.js. How to fetch or “call” data from one file to another? - vue.js

Question

I’m new to both Ionic and Vue.js. I’m taking advantage of this summer break to start learning both.
I’m building a mobile app for this purpose and so far, so good. However, I have found and issue that I hope you could help me with. Namely, how to fetch or “call” data from one file to another (Is it called routing?).
In my app, I am trying to start/open a function named myFunction() from one of the pages (quiz.vue) when I call it using v-on:click="myFunction3".
This function is located in a JS file called quizz.js, and it is located in the assets folder. This is its path: (“./assets/js/quizz.js”).
I have tried many things to make it work and finally it is working as it should. However, I think my solution is not optimal as it keeps throwing “Uncaught TypeErrors” in the console of the Developer’s Tool…even though it works.
My solution was to push the function inside methods: this.$router.push(myFunction3())
Also, when running the app, it says that myFunction() , and other functions in the same quizz.js file, “is define but never used”.
If you could advise me with anything, I would be most grateful. I am still a beginner so please explain it to me in as simple a manner as possible.
methods:{
openMenu(){
menuController.open("app-menu")
},
myFunction3(){
this.$router.push(myFunction3())
},
Below, the quizz.js file:
var mlhttp = new XMLHttpRequest();
mlhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
var myObj = JSON.parse(this.responseText);
const quiz = myObj.results[0]['question'];
const correctAnswer = myObj.results[0]['correct_answer'];
const incorrect = myObj.results[0]['incorrect_answers'];
incorrect.push(correctAnswer);
shuffle(incorrect);
document.getElementById("ans").innerHTML = quiz;
var text = "";
var val = 0;
var i;
for (i = 0; i < incorrect.length; i++) {
if(incorrect[i] == correctAnswer){
text += "<ion-button fill='outline' id='right' onClick='increment();myFunc();'/><b>" + incorrect[i] + "</b></ion-button></br>";
val = val + 1;
}else{
text += "<ion-button fill='outline' class='wrong' onClick='myFunc2();'/><b>" + incorrect[i] + "</b></ion-button></br>";
}
}
document.getElementById("ans5").innerHTML = text;
}
};
var j=0;
function myFunction3() {
document.getElementById("ans6").innerHTML = "";
mlhttp.open("GET", "https://opentdb.com/api.php?amount=1", true);
mlhttp.send();
j++;
document.getElementById('ans11').innerHTML=j;
}
function shuffle(array) {
for (let i = array.length - 1; i > 0; i--) {
let j = Math.floor(Math.random() * (i + 1));
[array[i], array[j]] = [array[j], array[i]];
}
}
function myFunc(){
document.getElementById("ans6").innerHTML = "<h1 style='color:green'><i class='fa fa-check'></i> That is correct!</h1>";
document.getElementById("right").style.color = "white";
document.getElementById("right").style.backgroundColor = "green";
var audio = new Audio('./assets/sound/win.mp3');
audio.play();
}
function myFunc2(){
document.getElementById("ans6").innerHTML = "<h1 style='color:red'><i class='fa fa-thumbs-down' ></i>Wrong Answer! </h1>";
document.getElementById("right").style.color = "white";
document.getElementById("right").style.backgroundColor = "green";
var x = document.getElementsByClassName("wrong");
var i;
for (i = 0; i < x.length; i++) {
x[i].style.backgroundColor = "rgba(255, 0, 0, 0.8)";
x[i].style.color = "white";
}
//document.getElementById("wrong").style.color = "red";
var audio = new Audio('./assets/sound/wrong.mp3');
audio.play();
}
var i=0;
function increment() {
i++;
document.getElementById('ans10').innerHTML=i;
}