one.js

const mySubmit = document.getElementById("mySubmit");
const myText = document.getElementById("myText");
const resultElement = document.getElementById("resultElement");
let age;

mySubmit.onclick = function () {

    age = myText.value;
    age = Number(age);
  if (age >= 100) {
    resultElement.textContent = `You are Too Old to enter this site`;
  } else if (age == 0) {
    resultElement.textContent = `You can't enter, you are just born`;
  } else if (age >= 18) {
    resultElement.textContent = `You are old Enough to enter the site`;
  } else if (age < 0) {
    resultElement.textContent = `Your age can't be below 0`;
  } else {
    resultElement.textContent = `you are must be 18+ to enter the site`;
  }
};