JSFiddle - React, Tailwind, and code Playground

HTML

<h1>Formulaire</h1>
    <form name="dmc">
<fieldset>
  <legend>Type de venue</legend>
  <input type="radio" required name="action" id="track" value="track" /><label for="track">Naissance</label>
  <input type="radio" required name="action" id="event" value="event"  /><label for="event">Achat</label><br />
</fieldset><br />
 <label>
    Date de naissance:
    <input type="date" name="bday" id="gday" required pattern="\d{4}-\d{2}-\d{2}" />
    <span class="validity"></span>
  </label>
  <label>
    Date d'arrivée à la ferme:
    <input type="date" name="cday" id="hday" required pattern="\d{4}-\d{2}-\d{2}" />
    <span class="validity"></span>
  </label><br /><br />
    <input type="text" id="Nom" name="name" placeholder="Nom">
      <br><br>
      <input type="text" id="email" name="email" placeholder="Email">
      <br><br>
<fieldset>
  <legend>sexe</legend>
  <input type="radio" required name="action" id="sex" value="track" /><label for="sex">M</label>
  <input type="radio" required name="action" id="sexe" value="event"  /><label for="sexe">F</label><br />
</fieldset><br />
<button type="button" onclick="afficher();">Texte du bouton</button>
    </form>

JavaScript

function afficher() {
var name = document.getElementById("Nom").value;
var email = document.getElementById("email").value;
 alert( name + '\n' + email )

}