app.js

document.querySelector('.get-jokes').addEventListener('click', getJokes);

function getJokes(e) {
  const number = document.querySelector('input[type="number"]').value;
  const xhr = new XMLHttpRequest();
  xhr.open('GET', `http://api.icndb.com/jokes/random/${number}`, true);
  xhr.onload = function () {
    if (this.status === 200) {
      const response = JSON.parse(this.responseText);

      let output = '';

      if (response.type === 'success') {
        response.value.forEach(function (joke) {
          output += `
            <li>${joke.joke}</li>
          `;
        });
      } else {
        output += '<li>Something went wrong</li>';
      }

      document.querySelector('.jokes').innerHTML = output;
    }
  }
  xhr.send();
  e.preventDefault();
}